This page copyright © 2003 Blackmask Online.
http://www.blackmask.com
The Botanic Garden A Poem in Two Parts. Part 1: The Economy of Vegetation
Produced by Jonathan Ingram, Robert Shimmin and Distributed Proofreaders
[Illustration: FLORA attired by the ELEMENTS]
THE
BOTANIC GARDEN;
A Poem, in Two Parts.
PART I.
CONTAINING
THE ECONOMY OF VEGETATION.
PART II.
THE LOVES OF THE PLANTS.
WITH
Philosophical Notes.
The general design of the following sheets is to inlist Imagination
under the banner of Science; and to lead her votaries from the
looser
analogies, which dress out the imagery of poetry, to the stricter,
ones
which form the ratiocination of philosophy. While their particular
design is to induce the ingenious to cultivate the knowledge of
Botany,
by introducing them to the vestibule of that delightful science,
and
recommending to their attention the immortal works of the
celebrated
Swedish Naturalist, LINNEUS.
In the first Poem, or Economy of Vegetation, the physiology of
Plants is
delivered; and the operation of the Elements, as far as they may be
supposed to affect the growth of Vegetables. In the second Poem, or
Loves of the Plants, the Sexual System of Linneus is explained,
with the
remarkable properties of many particular plants.
It may be proper here to apologize for many of the subsequent
conjectures on some articles of natural philosophy, as not being
supported by accurate investigation or conclusive experiments.
Extravagant theories however in those parts of philosophy, where
our
knowledge is yet imperfect, are not without their use; as they
encourage
the execution of laborious experiments, or the investigation of
ingenious deductions, to confirm or refute them. And since natural
objects are allied to each other by many affinities, every kind of
theoretic distribution of them adds to our knowledge by developing
some
of their analogies.
The Rosicrucian doctrine of Gnomes, Sylphs, Nymphs, and
Salamanders, was
thought to afford a proper machinery for a Botanic poem; as it is
probable, that they were originally the names of hieroglyphic
figures
representing the elements.
Many of the important operations of Nature were shadowed or
allegorized
in the heathen mythology, as the first Cupid springing from the Egg
of
Night, the marriage of Cupid and Psyche, the Rape of Proserpine,
the
Congress of Jupiter and Juno, Death and Resuscitation of Adonis,
&c.
many of which are ingeniously explained in the works of Bacon, Vol.
V.
p. 47. 4th Edit. London, 1778. The Egyptians were possessed of many
discoveries in philosophy and chemistry before the invention of
letters;
these were then expressed in hieroglyphic paintings of men and
animals;
which after the discovery of the alphabet were described and
animated by
the poets, and became first the deities of Egypt, and afterwards of
Greece and Rome. Allusions to those fables were therefore thought
proper
ornaments to a philosophical poem, and are occasionally introduced
either as represented by the poets, or preserved on the numerous
gems
and medallions of antiquity.
TO
THE AUTHOR
OF THE
POEM ON THE LOVES OF THE PLANTS.
BY THE REV. W.B. STEPHENS.
Oft tho' thy genius, D——! amply fraught
With native wealth, explore new worlds of mind;
Whence the bright ores of drossless wisdom brought,
Stampt by the Muse's hand, enrich mankind;
Tho' willing Nature to thy curious eye,
Involved in night, her mazy depths betray;
Till at their source thy piercing search descry
The streams, that bathe with Life our mortal clay;
Tho', boldly soaring in sublimer mood
Through trackless skies on metaphysic wings,
Thou darest to scan the approachless Cause of Good,
And weigh with steadfast hand the Sum of Things;
Yet wilt thou, charm'd amid his whispering bowers
Oft with lone step by glittering Derwent stray,
Mark his green foliage, count his musky flowers,
That blush or tremble to the rising ray;
While FANCY, seated in her rock-roof'd dell,
Listening the secrets of the vernal grove,
Breathes sweetest strains to thy symphonious shell,
And gives new echoes to the throne of Love.
Repton, Nov. 28, 1788.
The Genius of the place invites the Goddess of Botany. 1. She
descends,
is received by Spring, and the Elements, 59. Addresses the Nymphs
of
Fire. Star-light Night seen in the Camera Obscura, 81. I. Love
created
the Universe. Chaos explodes. All the Stars revolve. God. 97. II.
Shooting Stars. Lightning. Rainbow. Colours of the Morning and
Evening
Skies. Exterior Atmosphere of inflammable Air. Twilight.
Fire-balls.
Aurora Borealis. Planets. Comets. Fixed Stars. Sun's Orb, 115. III.
1.
Fires at the Earth's Centre. Animal Incubation, 137. 2. Volcanic
Mountains. Venus visits the Cyclops, 149. IV. Heat confined on the
Earth
by the Air. Phosphoric lights in the Evening. Bolognian Stone.
Calcined
Shells. Memnon's Harp, 173. Ignis fatuus. Luminous Flowers.
Glow-worm.
Fire-fly. Luminous Sea-insects. Electric Eel. Eagle armed with
Lightning, 189. V. 1. Discovery of Fire. Medusa, 209. 2. The
chemical
Properties of Fire. Phosphorus. Lady in Love, 223. 3. Gunpowder,
237.
VI. Steam-engine applied to Pumps, Bellows, Water-engines,
Corn-mills,
Coining, Barges, Waggons, Flying-chariots, 253. Labours of
Hercules.
Abyla and Calpe, 297. VII. 1. Electric Machine. Hesperian Dragon.
Electric kiss. Halo round the heads of Saints. Electric Shock.
Fairy-
rings, 335. 2. Death of Professor Richman, 371. 3. Franklin draws
Lightning from the Clouds. Cupid snatches the Thunder-bolt from
Jupiter,
383. VIII. Phosphoric Acid and Vital Heat produced in the Blood.
The
great Egg of Night, 399. IX. Western Wind unfettered. Naiad
released.
Frost assailed. Whale attacked, 421. X. Buds and Flowers expanded
by
Warmth, Electricity, and Light. Drawings with colourless
sympathetic
Inks; which appear when warmed by the Fire, 457. XI. Sirius.
Jupiter and
Semele. Northern Constellations. Ice-islands navigated into the
Tropic
Seas. Rainy Monsoons, 497. XII. Points erected to procure Rain.
Elijah
on Mount-Carmel, 549. Departure of the Nymphs of Fire like sparks
from
artificial Fireworks, 587.
THE
ECONOMY OF VEGETATION.
STAY YOUR RUDE STEPS! whose throbbing breasts infold
The legion-fiends of Glory, or of Gold!
Stay! whose false lips seductive simpers part,
While Cunning nestles in the harlot-heart!—
5 For you no Dryads dress the roseate bower,
For you no Nymphs their sparkling vases pour;
Unmark'd by you, light Graces swim the green,
And hovering Cupids aim their shafts, unseen.
“But THOU! whose mind the well-attemper'd ray
10 Of Taste and Virtue lights with purer day;
Whose finer sense each soft vibration owns
With sweet responsive sympathy of tones;
So the fair flower expands it's lucid form
To meet the sun, and shuts it to the storm;—
15 For thee my borders nurse the fragrant wreath,
My fountains murmur, and my zephyrs breathe;
Slow slides the painted snail, the gilded fly
Smooths his fine down, to charm thy curious eye;
On twinkling fins my pearly nations play,
20 Or win with sinuous train their trackless way;
My plumy pairs in gay embroidery dress'd
Form with ingenious bill the pensile nest,
To Love's sweet notes attune the listening dell,
And Echo sounds her soft symphonious shell.
[ So the fair flower. l. 13. It seems to have been the
original design
of the philosophy of Epicurus to render the mind exquisitely
sensible to
agreeable sensations, and equally insensible to disagreeable ones.]
25 “And, if with Thee some hapless Maid should stray,
Disasterous Love companion of her way,
Oh, lead her timid steps to yonder glade,
Whose arching cliffs depending alders shade;
There, as meek Evening wakes her temperate breeze,
30 And moon-beams glimmer through the trembling trees,
The rills, that gurgle round, shall soothe her ear,
The weeping rocks shall number tear for tear;
There as sad Philomel, alike forlorn,
Sings to the Night from her accustomed thorn;
35 While at sweet intervals each falling note
Sighs in the gale, and whispers round the grot;
The sister-woe shall calm her aching breast,
And softer slumbers steal her cares to rest.—
[Disasterous Love. l. 26. The scenery is taken from a
botanic garden
about a mile from Lichfield, where a cold bath was erected by Sir
John
Floyer. There is a grotto surrounded by projecting rocks, from the
edges
of which trickles a perpetual shower of water; and it is here
represented as adapted to love-scenes, as being thence a proper
residence for the modern goddess of Botany, and the easier to
introduce
the next poem on the Loves of the Plants according to the system of
Linneus.]
“Winds of the North! restrain your icy gales,
40 Nor chill the bosom of these happy vales!
Hence in dark heaps, ye gathering Clouds, revolve!
Disperse, ye Lightnings! and, ye Mists, dissolve!
—Hither, emerging from yon orient skies,
BOTANIC GODDESS! bend thy radiant eyes;
45 O'er these soft scenes assume thy gentle reign,
Pomona, Ceres, Flora in thy train;
O'er the still dawn thy placid smile effuse,
And with thy silver sandals print the dews;
In noon's bright blaze thy vermil vest unfold,
50 And wave thy emerald banner star'd with gold.”
Thus spoke the GENIUS, as He stept along,
And bade these lawns to Peace and Truth belong;
Down the steep slopes He led with modest skill
The willing pathway, and the truant rill,
55 Stretch'd o'er the marshy vale yon willowy mound,
Where shines the lake amid the tufted ground,
Raised the young woodland, smooth'd the wavy green,
And gave to Beauty all the quiet scene.—
She comes!—the GODDESS!—through the whispering air,
60 Bright as the morn, descends her blushing car;
Each circling wheel a wreath of flowers intwines,
And gem'd with flowers the silken harness shines;
The golden bits with flowery studs are deck'd,
And knots of flowers the crimson reins connect.—
65 And now on earth the silver axle rings,
And the shell sinks upon its slender springs;
Light from her airy seat the Goddess bounds,
And steps celestial press the pansied grounds.
Fair Spring advancing calls her feather'd quire,
70 And tunes to softer notes her laughing lyre;
Bids her gay hours on purple pinions move,
And arms her Zephyrs with the shafts of Love,
Pleased GNOMES, ascending from their earthy beds,
Play round her graceful footsteps, as she treads;
75 Gay SYLPHS attendant beat the fragrant air
On winnowing wings, and waft her golden hair;
Blue NYMPHS emerging leave their sparkling streams,
And FIERY FORMS alight from orient beams;
Musk'd in the rose's lap fresh dews they shed,
80 Or breathe celestial lustres round her head.
[Pleased Gnomes. l. 73. The Rosicrucian doctrine of Gnomes,
Sylphs,
Nymphs, and Salamanders affords proper machinery for a philosophic
poem;
as it is probable that they were originally the names of
hieroglyphic
figures of the Elements, or of Genii presiding over their
operations.
The Fairies of more modern days seem to have been derived from
them, and
to have inherited their powers. The Gnomes and Sylphs, as being
more
nearly allied to modern Fairies are represented as either male or
female, which distinguishes the latter from the Aurae of the Latin
Poets, which were only female; except the winds, as Zephyrus and
Auster,
may be supposed to have been their husbands.]
First the fine Forms her dulcet voice requires,
Which bathe or bask in elemental fires;
From each bright gem of Day's refulgent car,
From the pale sphere of every twinkling star,
85 From each nice pore of ocean, earth, and air,
With eye of flame the sparkling hosts repair,
Mix their gay hues, in changeful circles play,
Like motes, that tenant the meridian ray.—
So the clear Lens collects with magic power
90 The countless glories of the midnight hour;
Stars after stars with quivering lustre fall,
And twinkling glide along the whiten'd wall.—
Pleased, as they pass, she counts the glittering bands,
And stills their murmur with her waving hands;
95 Each listening tribe with fond expectance burns,
And now to these, and now to those, she turns.
I. “NYMPHS OF PRIMEVAL FIRE! YOUR vestal train
Hung with gold-tresses o'er the vast inane,
Pierced with your silver shafts the throne of Night,
100 And charm'd young Nature's opening eyes with light;
When LOVE DIVINE, with brooding wings unfurl'd,
Call'd from the rude abyss the living world.
”—LET THERE BE LIGHT!” proclaim'd the ALMIGHTY LORD,
Astonish'd Chaos heard the potent word;—
105 Through all his realms the kindling Ether runs,
And the mass starts into a million suns;
Earths round each sun with quick explosions burst,
And second planets issue from the first;
Bend, as they journey with projectile force,
110 In bright ellipses their reluctant course;
Orbs wheel in orbs, round centres centres roll,
And form, self-balanced, one revolving Whole.
—Onward they move amid their bright abode,
Space without bound, THE BOSOM OF THEIR GOD!
[Nymphs of primeval fire. l. 97. The fluid matter of heat is
perhaps
the most extensive element in nature; all other bodies are immersed
in
it, and are preserved in their present state of solidity or
fluidity by
the attraction of their particles to the matter of heat. Since all
known
bodies are contractible into less space by depriving them of some
portion of their heat, and as there is no part of nature totally
deprived of heat, there is reason to believe that the particles of
bodies do not touch, but are held towards each other by their self-
attraction, and recede from each other by their attraction to the
mass
of heat which surrounds them; and thus exist in an equilibrium
between
these two powers. If more of the matter of heat be applied to them,
they
recede further from each other, and become fluid; if still more be
applied, they take an aerial form, and are termed Gasses by the
modern
chemists. Thus when water is heated to a certain degree, it would
instantly assume the form of steam, but for the pressure of the
atmosphere, which prevents this change from taking place so easily;
the
same is true of quicksilver, diamonds, and of perhaps all other
bodies
in Nature; they would first become fluid, and then aeriform by
appropriated degrees of heat. On the contrary, this elastic matter
of
heat, termed Calorique in the new nomenclature of the French
Academicians, is liable to become consolidated itself in its
combinations with some bodies, as perhaps in nitre, and probably in
combustible bodies as sulphur and charcoal. See note on l. 232, of
this
Canto. Modern philosophers have not yet been able to decide whether
light and heat be different fluids, or modifications of the same
fluid,
as they have many properties in common. See note on l. 462 of this
Canto.]
[When Love Divine. l. 101. From having observed the gradual
evolution
of the young animal or plant from its egg or seed; and afterwards
its
successive advances to its more perfect state, or maturity;
philosophers
of all ages seem to have imagined, that the great world itself had
likewise its infancy and its gradual progress to maturity; this
seems to
have given origin to the very antient and sublime allegory of Eros,
or
Divine Love, producing the world from the egg of Night, as it
floated in
Chaos. See l. 419. of this Canto.
The external crust of the earth, as far as it has been exposed to
our
view in mines or mountains, countenances this opinion; since these
have
evidently for the most part had their origin from the shells of
fishes,
the decomposition of vegetables, and the recrements of other animal
materials, and must therefore have been formed progressively from
small
beginnings. There are likewise some apparently useless or
incomplete
appendages to plants and animals, which seem to shew they have
gradually
undergone changes from their original state; such as the stamens
without
anthers, and styles without stigmas of several plants, as mentioned
in
the note on Curcuma, Vol. II. of this work. Such is the halteres,
or
rudiments of wings of some two-winged insects; and the paps of male
animals; thus swine have four toes, but two of them are imperfectly
formed, and not long enough for use. The allantoide in some animals
seems to have become extinct; in others is above tenfold the size,
which
would seem necessary for its purpose. Buffon du Cochon. T. 6. p.
257.
Perhaps all the supposed monstrous births of Nature are remains of
their
habits of production in their former less perfect state, or
attempts
towards greater perfection.]
[Through all his realms. l. 105. Mr. Herschel has given a
very sublime
and curious account of the construction of the heavens with his
discovery of some thousand nebulae, or clouds of stars; many of
which
are much larger collections of stars, than all those put together,
which
are visible to our naked eyes, added to those which form the
galaxy, or
milky zone, which surrounds us. He observes that in the vicinity of
these clusters of stars there are proportionally fewer stars than
in
other parts of the heavens; and hence he concludes, that they have
attracted each other, on the supposition that infinite space was at
first equally sprinkled with them; as if it had at the beginning
been
filled with a fluid mass, which had coagulated. Mr. Herschel has
further
shewn, that the whole sidereal system is gradually moving round
some
centre, which may be an opake mass of matter, Philos. Trans. V.
LXXIV.
If all these Suns are moving round some great central body; they
must
have had a projectile force, as well as a centripetal one; and may
thence be supposed to have emerged or been projected from the
material,
where they were produced. We can have no idea of a natural power,
which
could project a Sun out of Chaos, except by comparing it to the
explosions or earthquakes owing to the sudden evolution of aqueous
or of
other more elastic vapours; of the power of which under
immeasurable
degrees of heat, and compression, we are yet ignorant.
It may be objected, that if the stars had been projected from a
Chaos by
explosions, that they must have returned again into it from the
known
laws of gravitation; this however would not happen, if the whole of
Chaos, like grains of gunpowder, was exploded at the same time, and
dispersed through infinite space at once, or in quick succession,
in
every possible direction. The same objection may be stated against
the
possibility of the planets having been thrown from the sun by
explosions; and the secondary planets from the primary ones; which
will
be spoken of more at large in the second Canto, but if the planets
are
supposed to have been projected from their suns, and the secondary
from
the primary ones, at the beginning of their course; they might be
so
influenced or diverted by the attractions of the suns, or sun, in
their
vicinity, as to prevent their tendency to return into the body,
from
which they were projected.
If these innumerable and immense suns thus rising out of Chaos are
supposed to have thrown out their attendant planets by new
explosions,
as they ascended; and those their respective satellites, filling in
a
moment the immensity of space with light and motion, a grander idea
cannot be conceived by the mind of man.]
115 II. “ETHEREAL POWERS! YOU chase the shooting stars,
Or yoke the vollied lightenings to your cars,
Cling round the aerial bow with prisms bright,
And pleased untwist the sevenfold threads of light;
Eve's silken couch with gorgeous tints adorn,
120 And fire the arrowy throne of rising Morn.
—OR, plum'd with flame, in gay battalion's spring
To brighter regions borne on broader wing;
Where lighter gases, circumfused on high,
Form the vast concave of exterior sky;
125 With airy lens the scatter'd rays assault,
And bend the twilight round the dusky vault;
Ride, with broad eye and scintillating hair,
The rapid Fire-ball through the midnight air;
Dart from the North on pale electric streams,
130 Fringing Night's sable robe with transient beams.
—OR rein the Planets in their swift careers,
Gilding with borrow'd light their twinkling spheres;
Alarm with comet-blaze the sapphire plain,
The wan stars glimmering through its silver train;
135 Gem the bright Zodiac, stud the glowing pole,
Or give the Sun's phlogistic orb to roll.
[Chase the shooting stars. l. 115. The meteors called
shooting stars,
the lightening, the rainbow, and the clouds, are phenomena of the
lower
regions of the atmosphere. The twilight, the meteors call'd
fire-balls,
or flying dragons, and the northern lights, inhabit the higher
regions
of the atmosphere. See additional notes, No. I.]
[Cling round the aerial bow. l. 117. See additional notes,
No. II]
[Eve's silken couch. l. 119. See additional notes, No. III.]
[Where lighter gases. l. 123. Mr. Cavendish has shewn that
the gas
called inflammable air, is at least ten times lighter than common
air;
Mr. Lavoisier contends, that it is one of the component parts of
water,
and is by him called hydrogene. It is supposed to afford their
principal
nourishment to vegetables and thence to animals, and is perpetually
rising from their decomposition; this source of it in hot climates,
and
in summer months, is so great as to exceed estimation. Now if this
light
gas passes through the atmosphere, without combining with it, it
must
compose another atmosphere over the aerial one; which must expand,
when
the pressure above it is thus taken away, to inconceivable tenuity.
If this supernatural gasseous atmosphere floats upon the aerial
one,
like ether upon water, what must happen? 1. it will flow from the
line,
where it will be produced in the greatest quantities, and become
much
accumulated over the poles of the earth; 2. the common air, or
lower
stratum of the atmosphere, will be much thinner over the poles than
at
the line; because if a glass globe be filled with oil and water,
and
whirled upon its axis, the centrifugal power will carry the heavier
fluid to the circumference, and the lighter will in consequence be
found
round the axis. 3. There may be a place at some certain latitude
between
the poles and the line on each side the equator, where the
inflammable
supernatant atmosphere may end, owing to the greater centrifugal
force
of the heavier aerial atmosphere. 4. Between the termination of the
aerial and the beginning of the gasseous atmosphere, the airs will
occasionally be intermixed, and thus become inflammable by the
electric
spark; these circumstances will assist in explaining the phenomena
of
fire-balls, northern lights, and of some variable winds, and long
continued rains.
Since the above note was first written, Mr. Volta I am informed has
applied the supposition of a supernatant atmosphere of inflammable
air,
to explain some phenomena in meteorology. And Mr. Lavoisier has
announced his design to write on this subject. Traite de Chimie,
Tom. I.
I am happy to find these opinions supported by such respectable
authority.]
[And bend the twilight. l. 126. The crepuscular atmosphere,
or the
region where the light of the sun ceases to be refracted to us, is
estimated by philosophers to be between 40 and 50 miles high, at
which
time the sun is about 18 degrees below the horizon; and the rarity
of
the air is supposed to be from 4,000 to 10,000 times greater than
at the
surface of the earth. Cotes's Hydrost. p. 123. The duration of
twilight
differs in different seasons and in different latitudes; in England
the
shortest twilight is about the beginning of October and of March;
in
more northern latitudes, where the sun never sinks more than 18
degrees,
below the horizon, the twilight continues the whole night. The time
of
its duration may also be occasionally affected by the varying
height of
the atmosphere. A number of observations on the duration of
twilight in
different latitudes might afford considerable information
concerning the
aerial strata in the higher regions of the atmosphere, and might
assist
in determining whether an exterior atmosphere of inflammable gas,
or
Hydrogene, exists over the aerial one.]
[Alarm with Comet-blaze. l. 133. See additional notes, No.
IV.]
[The Sun's phlogistic orb. l. 136. See additional notes, No.
V.]
III. NYMPHS! YOUR fine forms with steps impassive mock
Earth's vaulted roofs of adamantine rock;
Round her still centre tread the burning soil,
140 And watch the billowy Lavas, as they boil;
Where, in basaltic caves imprison'd deep,
Reluctant fires in dread suspension sleep;
Or sphere on sphere in widening waves expand,
And glad with genial warmth the incumbent land.
145 So when the Mother-bird selects their food
With curious bill, and feeds her callow brood;
Warmth from her tender heart eternal springs,
And pleased she clasps them with extended wings.
[Round the still centre. l. 139. Many philosophers have
believed that
the central parts of the earth consist of a fluid mass of burning
lava,
which they have called a subterraneous sun; and have supposed, that
it
contributes to the production of metals, and to the growth of
vegetables. See additional notes, No. VI.]
[Or sphere on sphere. l. 143. See additional notes, No.
VII.]
“YOU from deep cauldrons and unmeasured caves
150 Blow flaming airs, or pour vitrescent waves;
O'er shining oceans ray volcanic light,
Or hurl innocuous embers to the night.—
While with loud shouts to Etna Heccla calls,
And Andes answers from his beacon'd walls;
155 Sea-wilder'd crews the mountain-stars admire,
And Beauty beams amid tremendous fire.
[Hurl innocuous embers. l. 152. The immediate cause of
volcanic
eruptions is believed to be owing to the water of the sea, or from
lakes, or inundations, finding itself a passage into the
subterraneous
fires, which may lie at great depths. This must first produce by
its
coldness a condensation of the vapour there existing, or a vacuum,
and
thus occasion parts of the earth's crust or shell to be forced down
by
the pressure of the incumbent atmosphere. Afterwards the water
being
suddenly raised into steam produces all the explosive effects of
earthquakes. And by new accessions of water during the intervals of
the
explosions the repetition of the shocks is caused. These
circumstances
were hourly illustrated by the fountains of boiling water in
Iceland, in
which the surface of the water in the boiling wells sunk down low
before
every new ebullition.
Besides these eruptions occasioned by the steam of water, there
seems to
be a perpetual effusion of other vapours, more noxious and (as far
as it
is yet known) perhaps greatly more expansile than water from the
Volcanos in various parts of the world. As these Volcanos are
supposed
to be spiracula or breathing holes to the great subterraneous
fires, it
is probable that the escape of elastic vapours from them is the
cause,
that the earthquakes of modern days are of such small extent
compared to
those of antient times, of which vestiges remain in every part of
the
world, and on this account may be said not only to be innocuous,
but
useful.]
“Thus when of old, as mystic bards presume,
Huge CYCLOPS dwelt in Etna's rocky womb,
On thundering anvils rung their loud alarms,
160 And leagued with VULCAN forged immortal arms;
Descending VENUS sought the dark abode,
And sooth'd the labours of the grisly God.—
While frowning Loves the threatening falchion wield,
And tittering Graces peep behind the shield,
165 With jointed mail their fairy limbs o'erwhelm,
Or nod with pausing step the plumed helm;
With radiant eye She view'd the boiling ore,
Heard undismay'd the breathing bellows roar,
Admired their sinewy arms, and shoulders bare,
170 And ponderous hammers lifted high in air,
With smiles celestial bless'd their dazzled sight,
And Beauty blazed amid infernal night.
IV. “EFFULGENT MAIDS! YOU round deciduous day,
Tressed with soft beams, your glittering bands array;
175 On Earth's cold bosom, as the Sun retires,
Confine with folds of air the lingering fires;
O'er Eve's pale forms diffuse phosphoric light,
And deck with lambent flames the shrine of Night.
So, warm'd and kindled by meridian skies,
180 And view'd in darkness with dilated eyes,
BOLOGNA'S chalks with faint ignition blaze,
BECCARI'S shells emit prismatic rays.
So to the sacred Sun in MEMNON's fane,
Spontaneous concords quired the matin strain;
185 —Touch'd by his orient beam, responsive rings
The living lyre, and vibrates all it's strings;
Accordant ailes the tender tones prolong,
And holy echoes swell the adoring song.
[Confine with folds of air. l. 176. The air, like all other
bad
conductors of electricity, is known to be a bad conductor of heat;
and
thence prevents the heat acquired from the sun's rays by the
earth's
surface from being so soon dissipated, in the same manner as a
blanket,
which may be considered as a sponge filled with air, prevents the
escape
of heat from the person wrapped in it. This seems to be one cause
of the
great degree of cold on the tops of mountains, where the rarity of
the
air is greater, and it therefore becomes a better conductor both of
heat
and electricity. See note on Barometz, Vol. II. of this work.
There is however another cause to which the great coldness of
mountains
and of the higher regions of the atmosphere is more immediately to
be
ascribed, explained by Dr. Darwin in the Philos. Trans. Vol.
LXXVIII.
who has there proved by experiments with the air-gun and air-pump,
that
when any portion of the atmosphere becomes mechanically expanded,
it
absorbs heat from the bodies in its vicinity. And as the air which
creeps along the plains, expands itself by a part of the pressure
being
taken off when it ascends the sides of mountains; it at the same
time
attracts heat from the summits of those mountains, or other bodies
which
happen to be immersed in it, and thus produces cold. Hence he
concludes
that the hot air at the bottom of the Andes becomes temperate by
its own
rarefaction when it ascends to the city of Quito; and by its
further
rarefaction becomes cooled to the freezing point when it ascends to
the
snowy regions on the summits of those mountains. To this also he
attributes the great degree of cold experienced by the aeronauts in
their balloons; and which produces hail in summer at the height of
only
two or three miles in the atmosphere.]
[Diffuse phosphoric light. l. 177. I have often been induced
to
believe from observation, that the twilight of the evenings is
lighter
than that of the mornings at the same distance from noon. Some may
ascribe this to the greater height of the atmosphere in the
evenings
having been rarefied by the sun during the day; but as its density
must
at the same time be diminished, its power of refraction would
continue
the same. I should rather suppose that it may be owing to the
phosphorescent quality (as it is called) of almost all bodies; that
is,
when they have been exposed to the sun they continue to emit light
for a
considerable time afterwards. This is generally believed to arise
either
from such bodies giving out the light which they had previously
absorbed; or to the continuance of a slow combustion which the
light
they had been previously exposed to had excited. See the next
note.]
[Beccari's shells. l. 182. Beccari made many curious
experiments on
the phosphoric light, as it is called, which becomes visible on
bodies
brought into a dark room, after having been previously exposed to
the
sunshine. It appears from these experiments, that almost all
inflammable
bodies possess this quality in a greater or less degree; white
paper or
linen thus examined after having been exposed to the sunshine, is
luminous to an extraordinary degree; and if a person shut up in a
dark
room, puts one of his hands out into the sun's light for a short
time
and then retracts it, he will be able to see that hand distinctly
and
not the other. These experiments seem to countenance the idea of
light
being absorbed and again emitted from bodies when they are removed
into
darkness. But Beccari further pretended, that some calcareous
compositions when exposed to red, yellow, or blue light, through
coloured glasses, would on their being brought into a dark room
emit
coloured lights. This mistaken fact of Beccari's, Mr. Wilson
decidedly
refutes; and among many other curious experiments discovered, that
if
oyster-shells were thrown into a common fire and calcined for about
half
an hour, and then brought to a person who had previously been some
minutes in a dark room, that many of them would exhibit beautiful
irises
of prismatic colours, from whence probably arose Beccari's mistake.
Mr.
Wilson from hence contends, that these kinds of phosphori do not
emit
the light they had previously received, but that they are set on
fire by
the sun's rays, and continue for some time a slow combustion after
they
are withdrawn from the light. Wilson's Experiments on Phosphori.
Dodsley, 1775.
The Bolognian stone is a selenite, or gypsum, and has been long
celebrated for its phosphorescent quality after having been burnt
in a
sulphurous fire; and exposed when cold to the sun's light. It may
be
thus well imitated: Calcine oyster-shells half an hour, pulverize
them
when cold, and add one third part of flowers of sulphur, press them
close into a small crucible, and calcine them for an hour or
longer, and
keep the powder in a phial close stopped. A part of this powder is
to be
exposed for a minute or two to the sunbeams, and then brought into
a
dark room. The calcined Bolognian stone becomes a calcareous hepar
of
sulphur; but the calcined shells, as they contain the animal acid,
may
also contain some of the phosphorus of Kunkel.]
[In Memnon's fane. l. 183. See additional notes. No. VIII.]
“YOU with light Gas the lamps nocturnal feed,
190 Which dance and glimmer o'er the marshy mead;
Shine round Calendula at twilight hours,
And tip with silver all her saffron flowers;
Warm on her mossy couch the radiant Worm,
Guard from cold dews her love-illumin'd form,
195 From leaf to leaf conduct the virgin light,
Star of the earth, and diamond of the night.
You bid in air the tropic Beetle burn,
And fill with golden flame his winged urn;
Or gild the surge with insect-sparks, that swarm
200 Round the bright oar, the kindling prow alarm;
Or arm in waves, electric in his ire,
The dread Gymnotus with ethereal fire.—
Onward his course with waving tail he helms,
And mimic lightenings scare the watery realms,
205 So, when with bristling plumes the Bird of JOVE
Vindictive leaves the argent fields above,
Borne on broad wings the guilty world he awes,
And grasps the lightening in his shining claws.
[The lamps nocturnal. l. 189. The ignis fatuus or Jack a
lantern,
frequently alluded to by poets, is supposed to originate from the
inflammable air, or Hydrogene, given up from morasses; which being
of a
heavier kind from its impurity than that obtained from iron and
water,
hovers near the surface of the earth, and uniting with common air
gives
out light by its slow ignition. Perhaps such lights have no
existence,
and the reflection of a star on watery ground may have deceived the
travellers, who have been said to be bewildered by them? if the
fact was
established it would much contribute to explain the phenomena of
northern lights. I have travelled much in the night, in all seasons
of
the year, and over all kinds of soil, but never saw one of these
Will
o'wisps.]
[Shine round Calendula. l. 191. See note on Tropaeolum in
Vol. II.]
[The radiant Worm. l. 193. See additional notes, No. IX.]
[The dread Gymnotus. l. 202. The Gymnotus electricus is a
native of
the river of Surinam in South America; those which were brought
over to
England about eight years ago were about three or four feet long,
and
gave an electric shock (as I experienced) by putting one finger on
the
back near its head, and another of the opposite hand into the water
near
its tail. In their native country they are said to exceed twenty
feet in
length, and kill any man who approaches them in an hostile manner.
It is
not only to escape its enemies that this surprizing power of the
fish is
used, but also to take its prey; which it does by benumbing them
and
then devouring them before they have time to recover, or by
perfectly
killing them; for the quantity of the power seemed to be determined
by
the will or anger of the animal; as it sometimes struck a fish
twice
before it was sufficiently benumbed to be easily swallowed.
The organs productive of this wonderful accumulation of electric
matter
have been accurately dissected and described by Mr. J. Hunter.
Philos.
Trans. Vol. LXV. And are so divided by membranes as to compose a
very
extensive surface, and are supplied with many pairs of nerves
larger
than any other nerves of the body; but how so large a quantity is
so
quickly accumulated as to produce such amazing effects in a fluid
ill
adapted for the purpose is not yet satisfactorily explained. The
Torpedo
possesses a similar power in a less degree, as was shewn by Mr.
Walch,
and another fish lately described by Mr. Paterson. Philo. Trans.
Vol.
LXXVI.
In the construction of the Leyden-Phial, (as it is called) which is
coated on both sides, it is known, that above one hundred times the
quantity of positive electricity can be condensed on every square
inch
of the coating on one side, than could have been accumulated on the
same
surface if there had been no opposite coating communicating with
the
earth; because the negative electricity, or that part of it which
caused
its expansion, is now drawn off through the glass. It is also well
known, that the thinner the glass is (which is thus coated on both
sides
so as to make a Leyden-phial, or plate) the more electricity can be
condensed on one of its surfaces, till it becomes so thin as to
break,
and thence discharge itself.
Now it is possible, that the quantity of electricity condensible on
one
side of a coated phial may increase in some high ratio in respect
to the
thinness of the glass, since the power of attraction is known to
decrease as the squares of the distances, to which this
circumstance of
electricity seems to bear some analogy. Hence if an animal
membrane, as
thin as the silk-worm spins its silk, could be so situated as to be
charged like the Leyden bottle, without bursting, (as such thin
glass
would be liable to do,) it would be difficult to calculate the
immense
quantity of electric fluid, which might be accumulated on its
surface.
No land animals are yet discovered which possess this power, though
the
air would have been a much better medium for producing its effects;
perhaps the size of the necessary apparatus would have been
inconvenient
to land animals.]
[In his shining claws. l. 208. Alluding to an antique gem in
the
collection of the Grand Duke of Florence. Spence.]
V. 1. “NYMPHS! Your soft smiles uncultur'd man subdued,
210 And charm'd the Savage from his native wood;
You, while amazed his hurrying Hords retire
From the fell havoc of devouring FIRE,
Taught, the first Art! with piny rods to raise
By quick attrition the domestic blaze,
215 Fan with soft breath, with kindling leaves provide,
And lift the dread Destroyer on his side.
So, with bright wreath of serpent-tresses crown'd,
Severe in beauty, young MEDUSA frown'd;
Erewhile subdued, round WISDOM'S Aegis roll'd
220 Hiss'd the dread snakes, and flam'd in burnish'd gold;
Flash'd on her brandish'd arm the immortal shield,
And Terror lighten'd o'er the dazzled field.
[Of devouring fire. l. 212. The first and most important
discovery of
mankind seems to have been that of fire. For many ages it is
probable
fire was esteemed a dangerous enemy, known only by its dreadful
devastations; and that many lives must have been lost, and many
dangerous burns and wounds must have afflicted those who first
dared to
subject it to the uses of life. It is said that the tall monkies of
Borneo and Sumatra lie down with pleasure round any accidental fire
in
their woods; and are arrived to that degree of reason, that
knowledge of
causation, that they thrust into the remaining fire the half-burnt
ends
of the branches to prevent its going out. One of the nobles of the
cultivated people of Otaheita, when Captain Cook treated them with
tea,
catched the boiling water in his hand from the cock of the tea-urn,
and
bellowed with pain, not conceiving that water could become hot,
like red
fire.
Tools of steel constitute another important discovery in
consequence of
fire; and contributed perhaps principally to give the European
nations
so great superiority over the American world. By these two agents,
fire
and tools of steel, mankind became able to cope with the vegetable
kingdom, and conquer provinces of forests, which in uncultivated
countries almost exclude the growth of other vegetables, and of
those
animals which are necessary to our existence. Add to this, that the
quantity of our food is also increased by the use of fire, for some
vegetables become salutary food by means of the heat used in
cookery,
which are naturally either noxious or difficult of digestion; as
potatoes, kidney-beans, onions, cabbages. The cassava when made
into
bread, is perhaps rendered mild by the heat it undergoes, more than
by
expressing its superfluous juice. The roots of white bryony and of
arum,
I am informed lose much of their acrimony by boiling.]
[Young Medusa frowned. l. 218. The Egyptian Medusa is
represented on
antient gems with wings on her head, snaky hair, and a beautiful
countenance, which appears intensely thinking; and was supposed to
represent divine wisdom. The Grecian Medusa, on Minerva's shield,
as
appears on other gems, has a countenance distorted with rage or
pain,
and is supposed to represent divine vengeance. This Medusa was one
of
the Gorgons, at first very beautiful and terrible to her enemies;
Minerva turned her hair into snakes, and Perseus having cut off her
head
fixed it on the shield of that goddess; the sight of which then
petrified the beholders. Dannet Dict.]
2. NYMPHS! YOU disjoin, unite, condense, expand,
And give new wonders to the Chemist's hand;
225 On tepid clouds of rising steam aspire,
Or fix in sulphur all it's solid fire;
With boundless spring elastic airs unfold,
Or fill the fine vacuities of gold;
With sudden flash vitrescent sparks reveal,
230 By fierce collision from the flint and steel;
Or mark with shining letter KUNKEL's name
In the pale Phosphor's self-consuming flame.
So the chaste heart of some enchanted Maid
Shines with insidious light, by Love betray'd;
235 Round her pale bosom plays the young Desire,
And slow she wastes by self-consuming fire.
[Or fix in sulphur. l. 226. The phenomena of chemical
explosions
cannot be accounted for without the supposition, that some of the
bodies
employed contain concentrated or solid heat combined with them, to
which
the French Chemists have given the name of Calorique. When air is
expanded in the air-pump, or water evaporated into steam, they
drink up
or absorb a great quantity of heat; from this analogy, when
gunpowder is
exploded it ought to absorb much heat, that is, in popular
language, it
ought to produce a great quantity of cold. When vital air is united
with
phlogistic matter in respiration, which seems to be a slow
combustion,
its volume is lessened; the carbonic acid, and perhaps phosphoric
acid
are produced; and heat is given out; which according to the
experiments
of Dr. Crawford would seem to be deposited from the vital air. But
as
the vital air in nitrous acid is condensed from a light elastic gas
to
that of a heavy fluid, it must possess less heat than before. And
hence
a great part of the heat, which is given out in firing gunpowder, I
should suppose, must reside in the sulphur or charcoal.
Mr. Lavoisier has shewn, that vital air, or Oxygene, looses less of
its
heat when it becomes one of the component parts of nitrous acid,
than in
any other of its combinations; and is hence capable of giving out a
great quantity of heat in the explosion of gunpowder; but as there
seems
to be great analogy between the matter of heat, or Calorique, and
the
electric matter; and as the worst conductors of electricity are
believed
to contain the greatest quantity of that fluid; there is reason to
suspect that the worst conductors of heat may contain the most of
that
fluid; as sulphur, wax, silk, air, glass. See note on l. 174 of
this
Canto.]
[Vitrescent sparks. l. 229. When flints are struck against
other
flints they have the property of giving sparks of light; but it
seems to
be an internal light, perhaps of electric origin, very different
from
the ignited sparks which are struck from flint and steel. The
sparks
produced by the collision of steel with flint appear to be globular
particles of iron, which have been fused, and imperfectly scorified
or
vitrified. They are kindled by the heat produced by the collision;
but
their vivid light, and their fusion and vitrification are the
effects of
a combustion continued in these particles during their passage
through
the air. This opinion is confirmed by an experiment of Mr.
Hawksbee, who
found that these sparks could not be produced in the exhausted
receiver.
See Keir's Chemical Dict. art. Iron, and art. Earth vitrifiable.]
[The pale Phosphor. l. 232. See additionable notes, No. X.]
3. “YOU taught mysterious BACON to explore
Metallic veins, and part the dross from ore;
With sylvan coal in whirling mills combine
240 The crystal'd nitre, and the sulphurous mine;
Through wiry nets the black diffusion strain,
And close an airy ocean in a grain.—
Pent in dark chambers of cylindric brass
Slumbers in grim repose the sooty mass;
245 Lit by the brilliant spark, from grain to grain
Runs the quick fire along the kindling train;
On the pain'd ear-drum bursts the sudden crash,
Starts the red flame, and Death pursues the flash.—
Fear's feeble hand directs the fiery darts,
250 And Strength and Courage yield to chemic arts;
Guilt with pale brow the mimic thunder owns,
And Tyrants tremble on their blood-stain'd thrones.
[And close an airy ocean. l. 242. Gunpowder is plainly
described in
the works of Roger Bacon before the year 1267. He describes it in a
curious manner, mentioning the sulphur and nitre, but conceals the
charcoal in an anagram. The words are, sed tamen salis petrae
lure mope
can ubre, et sulphuris; et sic facies tonitrum, et
corruscationem, si
scias, artificium. The words lure mope can ubre are an anagram of
carbonum pulvere. Biograph. Britan. Vol. I. Bacon de Secretis
Operibus,
Cap. XI. He adds, that he thinks by an artifice of this kind Gideon
defeated the Midianites with only three hundred men. Judges, Chap.
VII.
Chamb. Dict. art. Gunpowder. As Bacon does not claim this as his
own
invention, it is thought by many to have been of much more antient
discovery.
The permanently elastic fluid generated in the firing of gunpowder
is
calculated by Mr. Robins to be about 244 if the bulk of the powder
be 1.
And that the heat generated at the time of the explosion occasions
the
rarefied air thus produced to occupy about 1000 times the space of
the
gunpowder. This pressure may therefore be called equal to 1000
atmospheres or six tons upon a square inch. As the suddenness of
this
explosion must contribute much to its power, it would seem that the
chamber of powder, to produce its greatest effect, should be
lighted in
the centre of it; which I believe is not attended to in the
manufacture
of muskets or pistols.
From the cheapness with which a very powerful gunpowder is likely
soon
to be manufactured from aerated marine acid, or from a new method
of
forming nitrous acid by means of mangonese or other calciform ores,
it
may probably in time be applied to move machinery, and supersede
the use
of steam.
There is a bitter invective in Don Quixot against the inventors of
gun-
powder, as it levels the strong with the weak, the knight cased in
steel
with the naked shepherd, those who have been trained to the sword,
with
those who are totally unskilful in the use of it; and throws down
all
the splendid distinctions of mankind. These very reasons ought to
have
been urged to shew that the discovery of gunpowder has been of
public
utility by weakening the tyranny of the few over the many.]
VI. NYMPHS! You erewhile on simmering cauldrons play'd,
And call'd delighted SAVERY to your aid;
255 Bade round the youth explosive STEAM aspire
In gathering clouds, and wing'd the wave with fire;
Bade with cold streams the quick expansion stop,
And sunk the immense of vapour to a drop.—
Press'd by the ponderous air the Piston falls
260 Resistless, sliding through it's iron walls;
Quick moves the balanced beam, of giant-birth,
Wields his large limbs, and nodding shakes the earth.
[Delighted Savery. l. 254. The invention of the steam-engine
for
raising water by the pressure of the air in consequence of the
condensation of steam, is properly ascribed to Capt. Savery; a
plate and
description of this machine is given in Harris's Lexicon Technicum,
art.
Engine. Though the Marquis of Worcester in his Century of
Inventions
printed in the year 1663 had described an engine for raising water
by
the explosive power of steam long before Savery's. Mr. Desegulier
affirms, that Savery bought up all he could procure of the books of
the
Marquis of Worcester, and destroyed them, professing himself then
to
have discovered the power of steam by accident, which seems to have
been
an unfounded slander. Savery applied it to the raising of water to
supply houses and gardens, but could not accomplish the draining of
mines by it. Which was afterwards done by Mr. Newcomen and Mr. John
Cowley at Dartmouth, in the year 1712, who added the piston.
A few years ago Mr. Watt of Glasgow much improved this machine, and
with
Mr. Boulton of Birmingham has applied it to variety of purposes,
such as
raising water from mines, blowing bellows to fuse the ore,
supplying
towns with water, grinding corn and many other purposes. There is
reason
to believe it may in time be applied to the rowing of barges, and
the
moving of carriages along the road. As the specific levity of air
is too
great for the support of great burthens by balloons, there seems no
probable method of flying conveniently but by the power of steam,
or
some other explosive material; which another half century may
probable
discover. See additional notes, No. XI.]
“The Giant-Power from earth's remotest caves
Lifts with strong arm her dark reluctant waves;
265 Each cavern'd rock, and hidden den explores,
Drags her dark coals, and digs her shining ores.—
Next, in close cells of ribbed oak confined,
Gale after gale, He crowds the struggling wind;
The imprison'd storms through brazen nostrils roar,
270 Fan the white flame, and fuse the sparkling ore.
Here high in air the rising stream He pours
To clay-built cisterns, or to lead-lined towers;
Fresh through a thousand pipes the wave distils,
And thirsty cities drink the exuberant rills.—
275 There the vast mill-stone with inebriate whirl
On trembling floors his forceful fingers twirl.
Whose flinty teeth the golden harvests grind,
Feast without blood! and nourish human-kind.
[Feast without blood! l. 278. The benevolence of the great
Author of
all things is greatly manifest in the sum of his works, as Dr.
Balguy
has well evinced in his pamphlet on Divine Benevolence asserted,
printed
for Davis, 1781. Yet if we may compare the parts of nature with
each
other, there are some circumstances of her economy which seem to
contribute more to the general scale of happiness than others. Thus
the
nourishment of animal bodies is derived from three sources: 1. the
milk
given from the mother to the offspring; in this excellent
contrivance
the mother has pleasure in affording the sustenance to the child,
and
the child has pleasure in receiving it. 2. Another source of the
food of
animals includes seeds or eggs; in these the embryon is in a torpid
or
insensible state, and there is along with it laid up for its early
nourishment a store of provision, as the fruit belonging to some
seeds,
and the oil and starch belonging to others; when these are consumed
by
animals the unfeeling seed or egg receives no pain, but the animal
receives pleasure which consumes it. Under this article may be
included
the bodies of animals which die naturally. 3. But the last method
of
supporting animal bodies by the destruction of other living
animals, as
lions preying upon lambs, these upon living vegetables, and mankind
upon
them all, would appear to be a less perfect part of the economy of
nature than those before mentioned, as contributing less to the sum
of
general happiness.]
“Now his hard hands on Mona's rifted crest,
280 Bosom'd in rock, her azure ores arrest;
With iron lips his rapid rollers seize
The lengthening bars, in thin expansion squeeze;
Descending screws with ponderous fly-wheels wound
The tawny plates, the new medallions round;
285 Hard dyes of steel the cupreous circles cramp,
And with quick fall his massy hammers stamp.
The Harp, the Lily and the Lion join,
And GEORGE and BRITAIN guard the sterling coin.
[Mona's rifted crest. l. 279. Alluding to the very valuable
copper-
mines in the isle of Anglesey, the property of the Earl of
Uxbridge.]
[With iron-lips. l. 281. Mr. Boulton has lately constructed
at Soho
near Birmingham, a most magnificent apparatus for Coining, which
has
cost him some thousand pounds; the whole machinery is moved by an
improved steam-engine, which rolls the copper for half-pence finer
than
copper has before been rolled for the purpose of making money; it
works
the coupoirs or screw-presses for cutting out the circular pieces
of
copper; and coins both the faces and edges of the money at the same
time, with such superior excellence and cheapness of workmanship,
as
well as with marks of such powerful machinery as must totally
prevent
clandestine imitation, and in consequence save many lives from the
hand
of the executioner; a circumstance worthy the attention of a great
minister. If a civic crown was given in Rome for preserving the
life of
one citizen, Mr. Boulton should be covered with garlands of oak! By
this
machinery four boys of ten or twelve years old are capable of
striking
thirty thousand guineas in an hour, and the machine itself keeps an
unerring account of the pieces struck.]
“Soon shall thy arm, UNCONQUER'D STEAM! afar
290 Drag the slow barge, or drive the rapid car;
Or on wide-waving wings expanded bear
The flying-chariot through the fields of air.
—Fair crews triumphant, leaning from above,
Shall wave their fluttering kerchiefs as they move;
295 Or warrior-bands alarm the gaping crowd,
And armies shrink beneath the shadowy cloud.
“So mighty HERCULES o'er many a clime
Waved his vast mace in Virtue's cause sublime,
Unmeasured strength with early art combined,
300 Awed, served, protected, and amazed mankind.—
First two dread Snakes at JUNO'S vengeful nod
Climb'd round the cradle of the sleeping God;
Waked by the shrilling hiss, and rustling sound,
And shrieks of fair attendants trembling round,
305 Their gasping throats with clenching hands he holds;
And Death untwists their convoluted folds.
Next in red torrents from her sevenfold heads
Fell HYDRA'S blood on Lerna's lake he sheds;
Grasps ACHELOUS with resistless force,
310 And drags the roaring River to his course;
Binds with loud bellowing and with hideous yell
The monster Bull, and threefold Dog of Hell.
[So mighty Hercules. l. 297. The story of Hercules seems of
great
antiquity, as appears from the simplicity of his dress and armour,
a
lion's skin and a club; and from the nature of many of his
exploits, the
destruction of wild beasts and robbers. This part of the history of
Hercules seems to have related to times before the invention of the
bow
and arrow, or of spinning flax. Other stories of Hercules are
perhaps of
later date, and appear to be allegorical, as his conquering the
river-
god Achilous, and bringing Cerberus up to day light; the former
might
refer to his turning the course of a river, and draining a morass,
and
the latter to his exposing a part of the superstition of the times.
The
strangling the lion and tearing his jaws asunder, are described
from a
statue in the Museum Florentinum, and from an antique gem; and the
grasping Anteus to death in his arms as he lifts him from the
earth, is
described from another antient cameo. The famous pillars of
Hercules
have been variously explained. Pliny asserts that the natives of
Spain
and of Africa believed that the mountains of Abyla and Calpe on
each
side of the straits of Gibraltar were the pillars of Hercules; and
that
they were reared by the hands of that god, and the sea admitted
between
them. Plin. Hist. Nat. p. 46. Edit. Manut. Venet. 1609.
If the passage between the two continents was opened by an
earthquake in
antient times, as this allegorical story would seem to countenance,
there must have been an immense current of water at first run into
the
Mediterranean from the Atlantic; since there is at present a strong
stream sets always from thence into the Mediterranean. Whatever may
be
the cause, which now constantly operates, so as to make the surface
of
the Mediterranean lower than that of the Atlantic, it must have
kept it
very much lower before a passage for the water through the
streights was
opened. It is probable before such an event took place, the coasts
and
islands of the Mediterranean extended much further into that sea,
and
were then for a great extent of country, destroyed by the floods
occasioned by the new rise of water, and have since remained
beneath the
sea. Might not this give rise to the flood of Deucalion? See note
Cassia, V. II. of this work.]
“Then, where Nemea's howling forests wave,
He drives the Lion to his dusky cave;
315 Seized by the throat the growling fiend disarms,
And tears his gaping jaws with sinewy arms;
Lifts proud ANTEUS from his mother-plains,
And with strong grasp the struggling Giant strains;
Back falls his fainting head, and clammy hair,
320 Writhe his weak limbs, and flits his life in air;—
By steps reverted o'er the blood-dropp'd fen
He tracks huge CACUS to his murderous den;
Where breathing flames through brazen lips he fled,
And shakes the rock-roof'd cavern o'er his head.
325 “Last with wide arms the solid earth He tears,
Piles rock on rock, on mountain mountain rears;
Heaves up huge ABYLA on Afric's sand,
Crowns with high CALPE Europe's saliant strand,
Crests with opposing towers the splendid scene,
330 And pours from urns immense the sea between.—
—Loud o'er her whirling flood Charybdis roars,
Affrighted Scylla bellows round his shores,
Vesuvio groans through all his echoing caves,
And Etna thunders o'er the insurgent waves.
335 VII. 1. NYMPHS! YOUR fine hands ethereal floods amass
From the warm cushion, and the whirling glass;
Beard the bright cylinder with golden wire,
And circumfuse the gravitating fire.
Cold from each point cerulean lustres gleam,
340 Or shoot in air the scintillating stream.
So, borne on brazen talons, watch'd of old
The sleepless dragon o'er his fruits of gold;
Bright beam'd his scales, his eye-balls blazed with ire,
And his wide nostrils breath'd inchanted fire.
[Ethereal floods amass. l. 335. The theory of the
accumulation of the
electric fluid by means of the glass-globe and cushion is difficult
to
comprehend. Dr. Franklin's idea of the pores of the glass being
opened
by the friction, and thence rendered capable of attracting more
electric
fluid, which it again parts with, as the pores contract again,
seems
analogous in some measure to the heat produced by the vibration, or
condensation of bodies, as when a nail is hammered or filed till it
becomes hot, as mentioned in additional Notes, No. VII. Some
philosophers have endeavoured to account for this phenomenon by
supposing the existence of two electric fluids which may be called
the
vitreous and resinous ones, instead of the plus and minus of the
same
ether. But its accumulation on the rubbed glass bears great analogy
to
its accumulation on the surface of the Leyden bottle, and can not
perhaps be explained from any known mechanical or chemical
principle.
See note on Gymnotus. l. 202, of this Canto.]
[Cold from each point. l. 339. See additional note, No.
XIII.]
345 “YOU bid gold-leaves, in crystal lantherns held,
Approach attracted, and recede repel'd;
While paper-nymphs instinct with motion rife,
And dancing fauns the admiring Sage surprize.
OR, if on wax some fearless Beauty stand,
350 And touch the sparkling rod with graceful hand;
Through her fine limbs the mimic lightnings dart,
And flames innocuous eddy round her heart;
O'er her fair brow the kindling lustres glare,
Blue rays diverging from her bristling hair;
355 While some fond Youth the kiss ethereal sips.
And soft fires issue from their meeting lips.
So round the virgin Saint in silver streams
The holy Halo shoots it's arrowy beams.
[You bid gold leaves. l. 345. Alluding to the very sensible
electrometer improved by Mr. Bennett, it consists of two slips of
gold-
leaf suspended from a tin cap in a glass cylinder, which has a
partial
coating without, communicating with the wooden pedestal. If a stick
of
sealing wax be rubbed for a moment on a dry cloth, and then held in
the
air at the distance of two or three feet from the cap of
this
instrument, the gold leaves seperate, such is its astonishing
sensibility to electric influence! (See Bennet on electricity,
Johnson,
Lond.) The nerves of sense of animal bodies do not seem to be
affected
by less quantities of light or heat!]
[The holy Halo. l. 358. I believe it is not known with
certainty at
what time the painters first introduced the luminous circle round
the
head to import a Saint or holy person. It is now become a part of
the
symbolic language of painting, and it is much to be wished that
this
kind of hieroglyphic character was more frequent in that art; as it
is
much wanted to render historic pictures both more intelligible, and
more
sublime; and why should not painting as well as poetry express
itself in
metaphor, or in indistinct allegory? A truly great modern painter
lately
endeavoured to enlarge the sphere of pictorial language, by putting
a
demon behind the pillow of a wicked man on his death bed. Which
unfortunately for the scientific part of painting, the cold
criticism of
the present day has depreciated; and thus barred perhaps the only
road
to the further improvement in this science.]
“YOU crowd in coated jars the denser fire,
360 Pierce the thin glass, and fuse the blazing wire;
Or dart the red flash through the circling band
Of youths and timorous damsels, hand in hand.
—Starts the quick Ether through the fibre-trains
Of dancing arteries, and of tingling veins,
365 Goads each fine nerve, with new sensation thrill'd,
Bends the reluctant limbs with power unwill'd;
Palsy's cold hands the fierce concussion own,
And Life clings trembling on her tottering throne.—
So from dark clouds the playful lightning springs,
370 Rives the firm oak, or prints the Fairy-rings.
[With new sensation thrill'd. l. 365. There is probably a
system of
nerves in animal bodies for the purpose of perceiving heat; since
the
degree of this fluid is so necessary to health that we become
presently
injured either by its access or defect; and because almost every
part of
our bodies is supplied with branches from different pairs of
nerves,
which would not seem necessary for their motion alone: It is
therefore
probable, that our sensation of electricity is only of its violence
in
passing through our system by its suddenly distending the muscles,
like
any other mechanical violence; and that it is general pain alone
that we
feel, and not any sensation analogous to the specific quality of
the
object. Nature may seem to have been niggardly to mankind in
bestowing
upon them so few senses; since a sense to have perceived
electricity,
and another to have perceived magnetism might have been of great
service
to them, many ages before these fluids were discovered by
accidental
experiment, but it is possible an increased number of senses might
have
incommoded us by adding to the size of our bodies.]
[Palsy's cold hands. l. 367. Paralytic limbs are in general
only
incapable of being stimulated into action by the power of the will;
since the pulse continues to beat and the fluids to be absorbed in
them;
and it commonly happens, when paralytic people yawn and stretch
themselves, (which is not a voluntary motion,) that the affected
limb
moves at the same time. The temporary motion of a paralytic limb is
likewise caused by passing the electric shock through it; which
would
seem to indicate some analogy between the electric fluid, and the
nervous fluid, which is seperated from the blood by the brain, and
thence diffused along the nerves for the purposes of motion and
sensation. It probably destroys life by its sudden expansion of the
nerves or fibres of the brain; in the same manner as it fuses
metals and
splinters wood or stone, and removes the atmosphere, when it passes
from
one object to another in a dense state.]
[Prints the Fairy rings. l. 370. See additional note No.
XIII.]
2. NYMPHS! on that day YE shed from lucid eyes.
Celestial tears, and breathed ethereal sighs!
When RICHMAN rear'd, by fearless haste betrayed,
The wiry rod in Nieva's fatal shade;—
375 Clouds o'er the Sage, with fringed skirts succeed,
Flash follows flash, the warning corks recede;
Near and more near He ey'd with fond amaze
The silver streams, and watch'd the saphire blaze;
Then burst the steel, the dart electric sped,
380 And the bold Sage lay number'd with the dead!—
NYMPHS! on that day YE shed from lucid eyes
Celestial tears, and breathed ethereal sighs!
[When Richman reared. l. 373. Dr. Richman Professor of
natural
philosophy at Petersburgh about the year 1763, elevated an
insulated
metallic rod to collect the aerial electricity, as Dr. Franklin had
previously done at Philadelphia; and as he was observing the
repulsion
of the balls of his electrometer approached too near the conductor,
and
receiving the lightening in his head with a loud explosion, was
struck
dead amidst his family.]
3. “YOU led your FRANKLIN to your glazed retreats,
Your air-built castles, and your silken seats;
385 Bade his bold arm invade the lowering sky,
And seize the tiptoe lightnings, ere they fly;
O'er the young Sage your mystic mantle spread,
And wreath'd the crown electric round his head.—
Thus when on wanton wing intrepid LOVE
390 Snatch'd the raised lightning from the arm of JOVE;
Quick o'er his knee the triple bolt He bent,
The cluster'd darts and forky arrows rent,
Snapp'd with illumin'd hands each flaming shaft,
His tingling fingers shook, and stamp'd, and laugh'd;
395 Bright o'er the floor the scatter'd fragments blaz'd,
And Gods retreating trembled as they gaz'd;
The immortal Sire, indulgent to his child,
Bow'd his ambrosial locks, and Heaven relenting smiled.
[You led your Franklin. l. 383. Dr. Franklin was the first
that
discovered that lightening consisted of electric matter, he
elevated a
tall rod with a wire wrapped round it, and fixing the bottom of a
rod
into a glass bottle, and preserving it from falling by means of
silk-
strings, he found it electrified whenever a cloud parted over it,
receiving sparks by his finger from it, and charging coated phials.
This
great discovery taught us to defend houses and ships and temples
from
lightning, and also to understand, that people are always
perfectly
safe in a room during a thunder storm if they keep themselves at
three
or four feet distance from the walls; for the matter of
lightning in
passing from the clouds to the earth, or from the earth to the
clouds,
runs through the walls of a house, the trunk of a tree, or other
elevated object; except there be some moister body, as an animal in
contact with them, or nearly so; and in that case the lightning
leaves
the wall or tree, and passes through the animal; but as it can pass
through metals with still greater facility, it will leave animal
bodies
to pass through metallic ones.
If a person in the open air be surprized by a thunderstorm, he will
know
his danger by observing on a second watch the time which passes
between
the flash and the crack, and reckoning a mile for every four
seconds and
a half, and a little more. For sound travels at the rate of 1142
feet in
a second of time, and the velocity of light through such small
distances
is not to be estimated. In these circumstances a person will be
safer by
lying down on the ground, than erect, and still safer if within a
few
feet of his horse; which being then a more elevated animal will
receive
the shock, in preference as the cloud passes over. See additional
notes,
No. XIII.]
[Intrepid Love. l. 389. This allegory is uncommonly
beautiful,
representing Divine Justice as disarmed by Divine Love, and
relenting of
his purpose. It is expressed on an agate in the Great Duke's
collection
at Florence. Spence.]
VIII. “When Air's pure essence joins the vital flood,
400 And with phosphoric Acid dyes the blood,
YOUR VIRGIN TRAINS the transient HEAT dispart,
And lead the soft combustion round the heart;
Life's holy lamp with fires successive feed,
From the crown'd forehead to the prostrate weed,
405 From Earth's proud realms to all that swim or sweep
The yielding ether or tumultuous deep.
You swell the bulb beneath the heaving lawn,
Brood the live seed, unfold the bursting spawn;
Nurse with soft lap, and warm with fragrant breath
410 The embryon panting in the arms of Death;
Youth's vivid eye with living light adorn,
And fire the rising blush of Beauty's golden morn.
[Transient heat dispart. l. 401. Dr. Crawford in his
ingenious work on
animal heat has endeavoured to prove, that during the combination
of the
pure part of the atmosphere with the phlogistic part of the blood,
that
much of the matter of the heat is given out from the air; and that
this
is the great and perpetual source of the heat of animals; to which
we
may add that the phosphoric acid is probably produced by this
combination; by which acid the colour of the blood is changed in
the
lungs from a deep crimson to a bright scarlet. There seems to be
however
another source of animal heat, though of a similar nature; and that
is
from the chemical combinations produced in all the glands; since by
whatever cause any glandular secretion is increased, as by friction
or
topical imflammation, the heat of that part becomes increased at
the
same time; thus after the hands have been for a time immersed in
snow,
on coming into a warm room, they become red and hot, without any
increased pulmonary action. BESIDES THIS there would seem to be
another
material received from the air by respiration; which is so
necessary to
life, that the embryon must learn to breathe almost within a minute
after
its birth, or it dies. The perpetual necessity of breathing shews,
that
the material thus acquired is perpetually consuming or escaping,
and on
that account requires perpetual renovation. Perhaps the spirit of
animation itself is thus acquired from the atmosphere, which if it
be
supposed to be finer or more subtle than the electric matter, could
not
long be retained in our bodies, and must therefore require
perpetual
renovation.]
“Thus when the Egg of Night, on Chaos hurl'd,
Burst, and disclosed the cradle of the world;
415 First from the gaping shell refulgent sprung
IMMORTAL LOVE, his bow celestial strung;—
O'er the wide waste his gaudy wings unfold,
Beam his soft smiles, and wave his curls of gold;—
With silver darts He pierced the kindling frame,
420 And lit with torch divine the ever-living flame.”
[Thus when the egg of Night. l. 413. There were two Cupids
belonging
to the antient mythology, one much elder than the other. The elder
cupid, or Eros, or divine Love, was the first that came out of the
great
egg of night, which floated in Chaos, and was broken by the horns
of the
celestial bull, that is, was hatched by the warmth of the spring.
He was
winged and armed, and by his arrows and torch pierced and vivified
all
things, producing life and joy. Bacon, Vol. V. p. 197. Quarto edit.
Lond. 1778. “At this time, (says Aristophanes,) sable-winged night
produced an egg, from whence sprung up like a blossom Eros, the
lovely,
the desirable, with his glossy golden wings.” Avibus. Bryant's
Mythology, Vol. II. p. 350. second edition. This interesting moment
of
this sublime allegory Mrs. Cosway has chosen for her very beautiful
painting. She has represented Eros or divine Love with large wings
having the strength of the eagle's wings, and the splendor of the
peacocks, with his hair floating in the form of flame, and with a
halo
of light vapour round his head; which illuminates the painting;
while he
is in the act of springing forwards, and with his hands separating
the
elements.]
IX. The GODDESS paused, admired with conscious pride
The effulgent legions marshal'd by her side,
Forms sphered in fire with trembling light array'd,
Ens without weight, and substance without shade;
425 And, while tumultuous joy her bosom warms,
Waves her white hand, and calls her hosts to arms,
“Unite, ILLUSTRIOUS NYMPHS! your radiant powers,
Call from their long repose the VERNAL HOURS.
Wake with soft touch, with rosy hands unbind
430 The struggling pinions of the WESTERN WIND;
Chafe his wan cheeks, his ruffled plumes repair,
And wring the rain-drops from his tangled hair.
Blaze round each frosted rill, or stagnant wave,
And charm the NAIAD from her silent cave;
435 Where, shrined in ice, like NIOBE she mourns,
And clasps with hoary arms her empty urns.
Call your bright myriads, trooping from afar,
With beamy helms, and glittering shafts of war;
In phalanx firm the FIEND OF FROST assail,
440 Break his white towers, and pierce his crystal mail;
To Zembla's moon-bright coasts the Tyrant bear,
And chain him howling to the Northern Bear.
[Of the Western Wind. l. 430. The principal frosts of this
country are
accompanied or produced by a N.E. wind, and the thaws by a S.W.
wind;
the reason of which is that the N.E. winds consist of regions of
air
brought from the north, which appear to acquire an easterly
direction as
they advance; and the S.W. winds consist of regions of air brought
from
the south, which appear to acquire a westerly direction as they
advance.
The surface of the earth nearer the pole moves slower than it does
in
our latitude; whence the regions of air brought from thence, move
slower, when they arrive hither, than the earth's surface with
which
they now become in contact; that is they acquire an apparent
easterly
direction, as the earth moves from west to east faster than this
new
part of its atmosphere. The S.W. winds on the contrary consist of
regions of air brought from the south, where the surface of the
earth
moves faster than in our latitude; and have therefore a westerly
direction when they arrive hither by their moving faster than the
surface of the earth, with which they are in contact; and in
general the
nearer to the west and the greater the velocity of these winds the
warmer they should be in respect to the season of the year, since
they
have been brought more expeditiously from the south, than those
winds
which have less westerly direction, and have thence been less
cooled in
their passage.
Sometimes I have observed the thaw to commence immediately on the
change
of the wind, even within an hour, if I am not mistaken, or sooner.
At
other times the S.W. wind has continued a day, or even two, before
the
thaw has commenced; during which time some of the frosty air, which
had
gone southwards, is driven back over us; and in consequence has
taken a
westerly direction, as well as a southern one. At other times I
have
observed a frost with a N.E. wind every morning, and a thaw with a
S.W.
wind every noon for several days together. See additional note,
XXXIII.]
[The Fiend of Frost. l. 439. The principal injury done to
vegetation
by frost is from the expansion of the water contained in the
vessels of
plants. Water converted into ice occupies a greater space than it
did
before, as appears by the bursting of bottles filled with water at
the
time of their freezing. Hence frost destroys those plants of our
island
first, which are most succulent; and the most succulent parts first
of
other plants; as their leaves and last year's shoots; the vessels
of
which are distended and burst by the expansion of their freezing
fluids,
while the drier or more resinous plants, as pines, yews, laurels,
and
other ever-greens, are less liable to injury from cold. The trees
in
vallies are on this account more injured by the vernal frosts than
those
on eminencies, because their early succulent shoots come out
sooner.
Hence fruit trees covered by a six-inch coping of a wall are less
injured by the vernal frosts because their being shielded from
showers
and the descending night-dews has prevented them from being moist
at the
time of their being frozen: which circumstance has given occasion
to a
vulgar error amongst gardeners, who suppose frost to descend.
As the common heat of the earth in this climate is 48 degrees,
those
tender trees which will bear bending down, are easily secured from
the
frost by spreading them upon the ground, and covering them with
straw or
fern. This particularly suits fig-trees, as they easily bear
bending to
the ground, and are furnished with an acrid juice, which secures
them
from the depredations of insects; but are nevertheless liable to be
eaten by mice. See additional notes, No. XII.]
“So when enormous GRAMPUS, issuing forth
From the pale regions of the icy North;
445 Waves his broad tail, and opes his ribbed mouth,
And seeks on winnowing fin the breezy South;
From towns deserted rush the breathless hosts,
Swarm round the hills, and darken all the coasts;
Boats follow boats along the shouting tides,
450 And spears and javelins pierce his blubbery sides;
Now the bold Sailor, raised on pointed toe,
Whirls the wing'd harpoon on the slimy foe;
Quick sinks the monster in his oozy bed,
The blood-stain'd surges circling o'er his head,
455 Steers to the frozen pole his wonted track,
And bears the iron tempest on his back.
X. “On wings of flame, ETHEREAL VIRGINS! sweep
O'er Earth's fair bosom, and complacent deep;
Where dwell my vegetative realms benumb'd,
460 In buds imprison'd, or in bulbs intomb'd,
Pervade, PELLUCID FORMS! their cold retreat,
Ray from bright urns your viewless floods of heat;
From earth's deep wastes electric torrents pour,
Or shed from heaven the scintillating shower;
465 Pierce the dull root, relax its fibre-trains,
Thaw the thick blood, which lingers in its veins;
Melt with warm breath the fragrant gums, that bind
The expanding foliage in its scaly rind;
And as in air the laughing leaflets play,
470 And turn their shining bosoms to the ray,
NYMPHS! with sweet smile each opening glower invite,
And on its damask eyelids pour the light.
[In buds imprison'd. l. 460. The buds and bulbs of plants
constitute
what is termed by Linneus the Hybernaculum, or winter cradle of the
embryon vegetable. The buds arise from the bark on the branches of
trees, and the bulbs from the caudex of bulbous-rooted plants, or
the
part from which the fibres of the root are produced, they are
defended
from too much moisture, and from frosts, and from the depredations
of
insects by various contrivances, as by scales, hairs, resinous
varnishes, and by acrid rinds.
The buds of trees are of two kinds, either flower-buds or leaf
buds; the
former of these produce their seeds and die; the latter produce
other
leaf buds or flower buds and die. So that all the buds of trees may
be
considered as annual plants, having their embryon produced during
the
preceeding summer. The same seems to happen with respect to bulbs;
thus
a tulip produces annually one flower-bearing bulb, sometimes two,
and
several leaf-bearing bulbs; and then the old root perishes. Next
year
the flower-bearing bulb produces seeds and other bulbs and
perishes;
while the leaf-bearing bulb, producing other bulbs only, perishes
likewise; these circumstances establish a strict analogy between
bulbs
and buds. See additional notes, No. XIV.]
[Viewless floods of heat. l. 462. The fluid matter of heat,
or
Calorique, in which all bodies are immersed, is as necessary to
vegetable as to animal existence. It is not yet determinable
whether
heat and light be different materials, or modifications of the same
materials, as they have some properties in common. They appear to
be
both of them equally necessary to vegetable health, since without
light
green vegetables become first yellow, that is, they lose the blue
colour, which contributed to produce the green; and afterwards they
also
lose the yellow and become white; as is seen in cellery blanched or
etiolated for the table by excluding the light from it.
The upper surface of leaves, which I suppose to be their organ of
respiration, seems to require light as well as air; since plants
which
grow in windows on the inside of houses are equally sollicitous to
turn
the upper side of their leaves to the light. Vegetables at the same
time
exsude or perspire a great quantity from their leaves, as animals
do
from their lungs; this perspirable matter as it rises from their
fine
vessels, (perhaps much finer than the pores of animal skins,) is
divided
into inconcievable tenuity; and when acted upon by the Sun's light
appears to be decomposed; the hydrogene becomes a part of the
vegetable,
composing oils or resins; and the Oxygene combined with light or
calorique ascends, producing the pure part of the atmosphere or
vital
air. Hence during the light of the day vegetables give up more pure
air
than their respiration injures; but not so in the night, even
though
equally exposed to warmth. This single fact would seem to shew,
that
light is essentially different from heat; and it is perhaps by its
combination with bodies, that their combined or latent heat is set
at
liberty, and becomes sensible. See additional note, XXXIV.]
[Electric torrents pour. l. 463. The influence of
electricity in
forwarding the germination of plants and their growth seems to be
pretty
well established; though Mr. Ingenhouz did not succeed in his
experiments, and thence doubts the success of those of others. And
though M. Rouland from his new experiments believes, that neither
positive nor negative electricity increases vegetation; both which
philosophers had previously been supporters of the contrary
doctrine;
for many other naturalists have since repeated their experiments
relative to this object, and their new results have confirmed their
former ones. Mr. D'Ormoy and the two Roziers have found the same
success
in numerous experiments which they have made in the last two years;
and
Mr. Carmoy has shewn in a convincing manner that electricity
accelerates
germination.
Mr. D'Ormoy not only found various seeds to vegetate sooner, and to
grow
taller which were put upon his insulated table and supplied with
electricity, but also that silk-worms began to spin much sooner
which
were kept electrified than those of the same hatch which were kept
in
the same place and manner, except that they were not electrified.
These
experiments of M. D'Ormoy are detailed at length in the Journal de
Physique of Rozier, Tom. XXXV. p. 270.
M. Bartholon, who had before written a tract on this subject, and
proposed ingenious methods for applying electricity to agriculture
and
gardening, has also repeated a numerous set of experiments; and
shews
both that natural electricity, as well as the artificial, increases
the
growth of plants, and the germination of seeds; and opposes Mr.
Ingenhouz by very numerous and conclusive facts. Ib. Tom. XXXV. p.
401.
Since by the late discoveries or opinions of the Chemists there is
reason to believe that water is decomposed in the vessels of
vegetables;
and that the Hydrogene or inflammable air, of which it in part
consists,
contributes to the nourishment of the plant, and to the production
of
its oils, rosins, gums, sugar, &c. and lastly as electricity
decomposes
water into these two airs termed Oxygene and Hydrogene, there is a
powerful analogy to induce us to believe that it accelerates or
contributes to the growth of vegetation, and like heat may possibly
enter into combination with many bodies, or form the basis of some
yet
unanalised acid.]
“So shall my pines, Canadian wilds that shade,
Where no bold step has pierc'd the tangled glade,
475 High-towering palms, that part the Southern flood
With shadowy isles and continents of wood,
Oaks, whose broad antlers crest Britannia's plain,
Or bear her thunders o'er the conquer'd main,
Shout, as you pass, inhale the genial skies,
480 And bask and brighten in your beamy eyes;
Bow their white heads, admire the changing clime,
Shake from their candied trunks the tinkling rime;
With bursting buds their wrinkled barks adorn,
And wed the timorous floret to her thorn;
485 Deep strike their roots, their lengthening tops revive,
And all my world of foliage wave, alive.
“Thus with Hermetic art the ADEPT combines
The royal acid with cobaltic mines;
Marks with quick pen, in lines unseen portrayed,
490 The blushing mead, green dell, and dusky glade;
Shades with pellucid clouds the tintless field,
And all the future Group exists conceal'd;
Till waked by fire the dawning tablet glows,
Green springs the herb, the purple floret blows,
495 Hills vales and woods in bright succession rise,
And all the living landscape charms his eyes.
[Thus with Hermetic art. l. 487. The sympathetic inks made
by Zaffre
dissolved in the marine and nitrous acids have this curious
property,
that being brought to the fire one of them becomes green, and the
other
red; but what is more wonderful, they again lose these colours,
(unless
the heat has been too great,) on their being again withdrawn from
the
fire. Fire-screens have been thus painted, which in the cold have
shewn
only the trunk and branches of a dead tree, and sandy hills, which
on
their approach to the fire have put forth green leaves and red
flowers,
and grass upon the mountains. The process of making these inks is
very
easy, take Zaffre, as sold by the druggists, and digest it in aqua
regia, and the calx of Cobalt will be dissolved; which solution
must be
diluted with a little common water to prevent it from making too
strong
an impression on the paper; the colour when the paper is heated
becomes
of a fine green-blue. If Zaffre or Regulus of Cobalt be dissolved
in the
same manner in spirit of nitre, or aqua fortis, a reddish colour is
produced on exposing the paper to heat. Chemical Dictionary by Mr.
Keir,
Art. Ink Sympathetic.]
XI. “With crest of gold should sultry SIRIUS glare,
And with his kindling tresses scorch the air;
With points of flame the shafts of Summer arm,
500 And burn the beauties he designs to warm;—
—So erst when JOVE his oath extorted mourn'd,
And clad in glory to the Fair return'd;
While Loves at forky bolts their torches light,
And resting lightnings gild the car of Night;
505 His blazing form the dazzled Maid admir'd,
Met with fond lips, and in his arms expir'd;—
NYMPHS! on light pinion lead your banner'd hosts
High o'er the cliffs of ORKNEY'S gulphy coasts;
Leave on your left the red volcanic light,
510 Which HECCLA lifts amid the dusky night;
Mark on the right the DOFRINE'S snow-capt brow,
Where whirling MAELSTROME roars and foams below;
Watch with unmoving eye, where CEPHEUS bends
His triple crown, his scepter'd hand extends;
515 Where studs CASSIOPE with stars unknown
Her golden chair, and gems her sapphire zone;
Where with vast convolution DRACO holds
The ecliptic axis in his scaly folds,
O'er half the skies his neck enormous rears,
520 And with immense meanders parts the BEARS;
Onward, the kindred BEARS with footstep rude
Dance round the Pole, pursuing and pursued.
[With stars unknown. l. 515. Alluding to the star which
appeared in
the chair of Cassiopea in the year 1572, which at first surpassed
Jupiter in magnitude and brightness, diminished by degrees and
disappeared in 18 months; it alarmed all the astronomers of the
age, and
was esteemed a comet by some.—Could this have been the Georgium
sidus?]
“There in her azure coif and starry stole,
Grey TWILIGHT sits, and rules the slumbering Pole;
525 Bends the pale moon-beams round the sparkling coast,
And strews with livid hands eternal frost.
There, NYMPHS! alight, array your dazzling powers,
With sudden march alarm the torpid Hours;
On ice-built isles expand a thousand sails,
530 Hinge the strong helms, and catch the frozen gales;
The winged rocks to feverish climates guide,
Where fainting Zephyrs pant upon the tide;
Pass, where to CEUTA CALPE'S thunder roars,
And answering echoes shake the kindred shores;
535 Pass, where with palmy plumes CANARY smiles,
And in her silver girdle binds her isles;
Onward, where NIGER'S dusky Naiad laves
A thousand kingdoms with prolific waves,
Or leads o'er golden sands her threefold train
540 In steamy channels to the fervid main,
While swarthy nations croud the sultry coast,
Drink the fresh breeze, and hail the floating Frost,
NYMPHS! veil'd in mist, the melting treasures steer,
And cool with arctic snows the tropic year.
545 So from the burning Line by Monsoons driven
Clouds sail in squadrons o'er the darken'd heaven;
Wide wastes of sand the gelid gales pervade,
And ocean cools beneath the moving shade.
[On ice-built isles. l. 529. There are many reasons to
believe from
the accounts of travellers and navigators, that the islands of ice
in
the higher northern latitudes as well as the Glaciers on the Alps
continue perpetually to increase in bulk. At certain times in the
ice-
mountains of Switzerland there happen cracks which have shewn the
great
thickness of the ice, as some of these cracks have measured three
or
four hundred ells deep. The great islands of ice in the northern
seas
near Hudson's bay have been observed to have been immersed above
one
hundred fathoms beneath the surface of the sea, and to have risen a
fifth or sixth part above the surface, and to have measured between
three and four miles in circumference. Phil. Trans. No. 465. Sect.
2.
Dr. Lister endeavoured to shew that the ice of sea-water contains
some
salt and perhaps less air than common ice, and that it is therefore
much
more difficult of solution; whence he accounts for the perpetual
and
great increase of these floating islands of ice. Philos. Trans. No.
169.
As by a famous experiment of Mr. Boyles it appears that ice
evaporates
very fast in severe frosty weather when the wind blows upon it; and
as
ice in a thawing state is known to contain six times more cold than
water at the same degree of sensible coldness, it is easy to
understand
that winds blowing over islands and continents of ice perhaps much
below
nothing on Farenheit's scale, and coming from thence into our
latitude
must bring great degrees of cold along with them. If we add to this
the
quantity of cold produced by the evaporation of the water as well
as by
the solution of the ice, we cannot doubt but that the northern ice
is
the principle source of the coldness of our winters, and that it is
brought hither by the regions of air blowing from the north, and
which
take an apparent easterly direction by their coming to a part of
the
surface of the earth which moves faster than the latitude they come
from. Hence the increase of the ice in the polar regions by
increasing
the cold of our climate adds at the same time to the bulk of the
Glaciers of Italy and Switzerland.
If the nations who inhabit this hemisphere of the globe, instead of
destroying their sea-men and exhausting their wealth in unnecessary
wars, could be induced to unite their labours to navigate these
immense
masses of ice into the more southern oceans, two great advantages
would
result to mankind, the tropic countries would be much cooled by
their
solution, and our winters in this latitude would be rendered much
milder
for perhaps a century or two, till the masses of ice became again
enormous.
Mr. Bradley describes the cold winds and wet weather which
sometimes
happen in May and June to the solution of ice-islands accidentally
floating from the north. Treatise on Husbandry and Gardening, Vol.
II.
p. 437. And adds, that Mr. Barham about the year 1718, in his
voyage
from Jamaica to England in the beginning of June, met with
ice-islands
coming from the north, which were surrounded with so great a fog
that
the ship was in danger of striking upon them, and that one of them
measured fifty miles in length.
We have lately experienced an instance of ice-islands brought from
the
Southern polar regions, on which the Guardian struck at the
beginning of
her passage from the Cape of Good Hope towards Botany Bay, on
December
22, 1789. These islands were involved in mist, were about one
hundred
and fifty fathoms long, and about fifty fathoms above the surface
of the
water. A part from the top of one of them broke off and fell into
the
sea, causing an extraordinary commotion in the water and a thick
smoke
all round it.]
[Threefold train. l. 539. The river Niger after traversing
an immense
tract of populous country is supposed to divide itself into three
other
great rivers. The Rio Grande, the Gambia, and the Senegal.
Gold-dust is
obtained from the sands of these rivers.]
[Wide wastes of sand. l. 547. When the sun is in the
Southern tropic
36 deg. distant from the zenith, the thermometer is seldom lower
than 72
deg. at Gondar in Abyssinia, but it falls to 60 or 53 deg. when the
sun
is immediately vertical; so much does the approach of rain
counteract
the heat of the sun. Bruce's Travels, Vol. 3. p. 670.]
XII. Should SOLSTICE, stalking through the sickening bowers,
550 Suck the warm dew-drops, lap the falling showers;
Kneel with parch'd lip, and bending from it's brink
From dripping palm the scanty river drink;
NYMPHS! o'er the soil ten thousand points erect,
And high in air the electric flame collect.
555 Soon shall dark mists with self-attraction shroud
The blazing day, and sail in wilds of cloud;
Each silvery Flower the streams aerial quaff,
Bow her sweet head, and infant Harvest laugh.
[Ten thousand points erect. l. 553. The solution of water in
air or in
calorique, seems to acquire electric matter at the same time, as
appears
from an experiment of Mr. Bennet. He put some live coals into an
insulated funnel of metal, and throwing on them a little water
observed
that the ascending steam was electrised plus, and the water which
descended through the funnel was electrised minus. Hence it appears
that
though clouds by their change of form may sometimes become
electrised
minus yet they have in general an accumulation of electricity. This
accumulation of electric matter also evidently contributes to
support
the atmospheric vapour when it is condensed into the form of
clouds,
because it is seen to descend rapidly after the flashes of
lightning
have diminished its quantity; whence there is reason to conclude
that
very numerous metallic rods with fine points erected high in the
air
might induce it at any time to part with some of its water.
If we may trust the theory of Mr. Lavoisier concerning the
composition
and decomposition of water, there would seem another source of
thunder-
showers; and that is, that the two gasses termed oxygene gas or
vital
air, and hydrogene gas or inflammable air, may exist in the summer
atmosphere in a state of mixture but not of combination, and that
the
electric spark or flash of lightning may combine them and produce
water
instantaneously.]
“Thus when ELIJA mark'd from Carmel's brow
560 In bright expanse the briny flood below;
Roll'd his red eyes amid the scorching air,
Smote his firm breast, and breathed his ardent prayer;
High in the midst a massy altar stood,
And slaughter'd offerings press'd the piles of wood;
565 While ISRAEL'S chiefs the sacred hill surround,
And famish'd armies crowd the dusty ground;
While proud Idolatry was leagued with dearth,
And wither'd famine swept the desert earth.—
“OH, MIGHTY LORD! thy woe-worn servant hear,
570 “Who calls thy name in agony of prayer;
“Thy fanes dishonour'd, and thy prophets slain,
“Lo! I alone survive of all thy train!—
“Oh send from heaven thy sacred fire,—and pour
“O'er the parch'd land the salutary shower,—
575 “So shall thy Priest thy erring flock recal,—
“And speak in thunder, “THOU ART LORD OF ALL.”—
He cried, and kneeling on the mountain-sands,
Stretch'd high in air his supplicating hands.
—Descending flames the dusky shrine illume;
580 Fire the wet wood, the sacred bull consume;
Wing'd from the sea the gathering mists arise,
And floating waters darken all the skies;
The King with shifted reins his chariot bends,
And wide o'er earth the airy flood descends;
585 With mingling cries dispersing hosts applaud,
And shouting nations own THE LIVING GOD.”
The GODDESS ceased,—the exulting tribes obey,
Start from the soil, and win their airy way;
The vaulted skies with streams of transient rays
590 Shine, as they pass, and earth and ocean blaze.
So from fierce wars when lawless Monarch's cease,
Or Liberty returns with laurel'd Peace;
Bright fly the sparks, the colour'd lustres burn,
Flash follows f
595 Blue serpents sweep along the dusky air,
Imp'd by long trains of scintillating hair;
Red rockets rise, loud cracks are heard on high,
And showers of stars rush headlong from the sky,
Burst, as in silver lines they hiss along,
600 And the quick flash unfolds the gazing throng.
Argument of the Second Canto.
Address to the Gnomes. I. The Earth thrown from a volcano of the
Sun;
it's atmosphere and ocean; it's journey through the zodiac;
vicissitude
of day-light, and of seasons, 11. II. Primeval islands. Paradise,
or the
golden Age. Venus rising from the sea, 33. III. The first great
earthquakes; continents raised from the sea; the Moon thrown from a
volcano, has no atmosphere, and is frozen; the earth's diurnal
motion
retarded; it's axis more inclined; whirls with the moon round a new
centre. 67. IV. Formation of lime-stone by aqueous solution;
calcareous
spar; white marble; antient statue of Hercules resting from his
labours.
Antinous. Apollo of Belvidere. Venus de Medici. Lady Elizabeth
Foster,
and Lady Melbourn by Mrs. Damer. 93. V. 1. Of morasses. Whence the
production of Salt by elutriation. Salt-mines at Cracow, 115. 2.
Production of nitre. Mars and Venus caught by Vulcan, 143. 3.
Production
of iron. Mr. Michel's improvement of artificial magnets. Uses of
Steel
in agriculture, navigation, war, 183. 4. Production of acids,
whence
Flint. Sea-sand. Selenite. Asbestus. Fluor. Onyx, Agate, Mocho,
Opal,
Sapphire, Ruby, Diamond. Jupiter and Europa, 215. VI. 1. New
subterraneous fires from fermentation. Production of Clays;
manufacture
of Porcelain in China; in Italy; in England. Mr. Wedgwood's works
at
Etruria in Staffordshire. Cameo of a Slave in Chains; of Hope.
Figures
on the Portland or Barberini vase explained, 271. 2. Coal; Pyrite;
Naphtha; Jet; Amber. Dr. Franklin's discovery of disarming the
Tempest
of it's lightning. Liberty of America; of Ireland; of France, 349.
VII.
Antient central subterraneous fires. Production of Tin, Copper,
Zink,
Lead, Mercury, Platina, Gold and Silver. Destruction of Mexico.
Slavery
of Africa, 395. VIII. Destruction of the armies of Cambyses, 431.
IX.
Gnomes like stars of an Orrery. Inroads of the Sea stopped. Rocks
cultivated. Hannibal passes the Alps, 499. X. Matter circulates.
Manures
to Vegetables like Chyle to Animals. Plants rising from the Earth.
St.
Peter delivered from Prison, 537. XI. Transmigration of matter,
565.
Death and resuscitation of Adonis, 575. Departure of the Gnomes,
601.
THE
ECONOMY OF VEGETATION.
AND NOW THE GODDESS with attention sweet
Turns to the GNOMES, that circle round her feet;
Orb within orb approach the marshal'd trains,
And pigmy legions darken all the plains;
5 Thrice shout with silver tones the applauding bands,
Bow, ere She speaks, and clap their fairy hands.
So the tall grass, when noon-tide zephyr blows,
Bends it's green blades in undulating rows;
Wide o'er the fields the billowy tumult spreads,
10 And rustling harvests bow their golden heads.
I. “GNOMES! YOUR bright forms, presiding at her birth,
Clung in fond squadrons round the new-born EARTH;
When high in ether, with explosion dire,
From the deep craters of his realms of fire,
15 The whirling Sun this ponderous planet hurl'd,
And gave the astonish'd void another world.
When from it's vaporous air, condensed by cold,
Descending torrents into oceans roll'd;
And fierce attraction with relentless force
20 Bent the reluctant wanderer to it's course.
[From the deep craters. l. 14. The existence of solar
volcanos is
countenanced by their analogy to terrestrial, and lunar volcanos;
and by
the spots on the sun's disk, which have been shewn by Dr. Wilson to
be
excavations through its luminous surface, and may be supposed to be
the
cavities from whence the planets and comets were ejected by
explosions.
See additional notes, No. XV. on solar volcanos.]
[When from its vaporous air. l. 17. If the nucleus of the
earth was
thrown out from the sun by an explosion along with as large a
quantity
of surrounding hot vapour as its attraction would occasion to
accompany
it, the ponderous semi-fluid nucleus would take a spherical form
from
the attraction of its own parts, which would become an oblate
spheroid
from its diurnal revolution. As the vapour cooled the water would
be
precipitated, and an ocean would surround the spherical nucleus
with a
superincumbent atmosphere. The nucleus of solar lava would likewise
become harder as it became cooler. To understand how the strata of
the
earth were afterwards formed from the sediments of this
circumfluent
ocean the reader is referred to an ingenious Treatise on the Theory
of
the Earth by Mr. Whitehurst, who was many years a watch-maker and
engineer at Derby, but whose ingenuity, integrity, and humanity,
were
rarely equalled in any station of life.]
“Where yet the Bull with diamond-eye adorns
The Spring's fair forehead, and with golden horns;
Where yet the Lion climbs the ethereal plain,
And shakes the Summer from his radiant mane;
25 Where Libra lifts her airy arm, and weighs,
Poised in her silver ballance, nights and days;
With paler lustres where Aquarius burns,
And showers the still snow from his hoary urns;
YOUR ardent troops pursued the flying sphere,
30 Circling the starry girdle of the year;
While sweet vicissitudes of day and clime
Mark'd the new annals of enascent Time.
II. “You trod with printless step Earth's tender globe,
While Ocean wrap'd it in his azure robe;
35 Beneath his waves her hardening strata spread,
Raised her PRIMEVAL ISLANDS from his bed,
Stretch'd her wide lawns, and sunk her winding dells,
And deck'd her shores with corals, pearls, and shells.
[While ocean wrap'd. l. 34. See additional notes, No. XVI.
on the
production of calcareous earth.]
[Her hardening srata spread. l. 35. The granite, or
moor-stone, or
porphory, constitute the oldest part of the globe, since the
limestone,
shells, coralloids, and other sea-productions rest upon them; and
upon
these sea-productions are found clay, iron, coal, salt, and
siliceous
sand or grit-stone. Thus there seem to be three divisions of the
globe
distinctly marked; the first I suppose to have been the original
nucleus
of the earth, or lava projected from the sun; 2. over this lie the
recrements of animal and vegetable matter produced in the ocean;
and, 3.
over these the recrements of animal and vegetable matter produced
upon
the land. Besides these there are bodies which owe their origin to
a
combination of those already mentioned, as siliceous sand, fluor,
alabaster; which seem to have derived their acids originally from
the
vegetable kingdom, and their earthy bases from sea-productions. See
additional notes, No. XVI. on calcareous earth.]
[Raised her primeval islands. l. 36. The nucleus of the
earth, still
covered with water, received perpetual increase by the immense
quantities of shells and coralloids either annually produced and
relinquishied, or left after the death of the animals. These would
gradually by their different degrees of cohesion be some of them
more
and others less removable by the influence of solar tides, and
gentle
tropical breezes, which then must have probably extended from one
pole
to the other; for it is supposed the moon was not yet produced, and
that
no storms or unequal winds had yet existence.
Hence then the primeval islands had their gradual origin, were
raised
but a few feet above the level of the sea, and were not exposed to
the
great or sudden variations of heat and cold, as is so well
explained in
Mr. Whitehurst's Theory of the Earth, chap. xvi. Whence the
paradise of
the sacred writers, and the golden age of the profane ones, seems
to
have had a real existence. As there can be no rainbow, when the
heavens
are covered with clouds, because the sun-beams are then precluded
from
falling upon the rain-drops opposite to the eye of the spectator,
the
rainbow is a mark of gentle or partial showers. Mr. Whitehurst has
endeavoured to show that the primitive islands were only moistened
by
nocturnal dews and not by showers, as occurs at this day to the
Delta of
Egypt; and is thence of opinion, that the rainbow had no existence
till
after the production of mountains and continents. As the salt of
the sea
has been gradually accumulating, being washed down into it from the
recrements of animal and vegetable bodies, the sea must originally
have
been as fresh as river water; and as it is not yet saturated with
salt,
must become annually more saline. See note on l. 119 of this
Canto.]
“O'er those blest isles no ice-crown'd mountains tower'd,
40 No lightnings darted, and no tempests lower'd;
Soft fell the vesper-drops, condensed below,
Or bent in air the rain-refracted bow;
Sweet breathed the zephyrs, just perceiv'd and lost;
And brineless billows only kiss'd the coast;
45 Round the bright zodiac danced the vernal hours,
And Peace, the Cherub, dwelt in mortal bowers!
“So young DIONE, nursed beneath the waves,
And rock'd by Nereids in their coral caves,
Charm'd the blue sisterhood with playful wiles,
50 Lisp'd her sweet tones, and tried her tender smiles.
Then, on her beryl throne by Triton's borne,
Bright rose the Goddess like the Star of morn;
When with soft fires the milky dawn He leads,
And wakes to life and love the laughing meads;—
55 With rosy fingers, as uncurl'd they hung
Round her fair brow, her golden locks she wrung;
O'er the smooth surge on silver sandals flood,
And look'd enchantment on the dazzled flood.—
The bright drops, rolling from her lifted arms,
60 In slow meanders wander o'er her charms,
Seek round her snowy neck their lucid track,
Pearl her white shoulders, gem her ivory back,
Round her fine waist and swelling bosom swim,
And star with glittering brine each crystal limb.—
65 —The immortal form enamour'd Nature hail'd,
And Beauty blazed to heaven and earth, unvail'd.
[So young Dione. l. 47. There is an antient gem representing
Venus
rising out of the ocean supported by two Tritons. From the
formality of
the design it would appear to be of great antiquity before the
introduction of fine taste into the world. It is probable that this
beautiful allegory was originally an hieroglyphic picture (before
the
invention of letters) descriptive of the formation of the earth
from the
ocean, which seems to have been an opinion of many of the most
antient
philosophers.]
III. “You! who then, kindling after many an age,
Saw with new fires the first VOLCANO rage,
O'er smouldering heaps of livid sulphur swell
70 At Earth's firm centre, and distend her shell,
Saw at each opening cleft the furnace glow,
And seas rush headlong on the gulphs below.—
GNOMES! how you shriek'd! when through the troubled air
Roar'd the fierce din of elemental war;
75 When rose the continents, and sunk the main,
And Earth's huge sphere exploding burst in twain.—
GNOMES! how you gazed! when from her wounded side
Where now the South-Sea heaves its waste of tide,
Rose on swift wheels the MOON'S refulgent car,
80 Circling the solar orb; a sister-star,
Dimpled with vales, with shining hills emboss'd,
And roll'd round Earth her airless realms of frost.
[The first volcano. l. 68. As the earth before the existence
of
earthquakes was nearly level, and the greatest part of it covered
with
sea; when the first great fires began deep in the internal parts of
it,
those parts would become much expanded; this expansion would be
gradually extended, as the heat increased, through the whole
terraqueous
globe of 7000 miles diameter; the crust would thence in many places
open
into fissures, which by admitting the sea to flow in upon the fire,
would produce not only a quantity of steam beyond calculation by
its
expansion, but would also by its decomposition produce inflammable
air
and vital air in quantities beyond conception, sufficient to effect
those violent explosions, the vestiges of which all over the world
excite our admiration and our study; the difficulty of
understanding how
subterraneous fires could exist without the presence of air has
disappeared since Dr. Priestley's discoveries of such great
quantities
of pure air which constitute all the acids, and consequently exist
in
all saline bodies, as sea-salt, nitre, lime-stone, and in all
calciform
ores, as manganese, calamy, ochre, and other mineral substances.
See an
ingenious treatise by Mr. Michel on earthquakes in the Philos.
Trans.
In these first tremendous ignitions of the globe, as the continents
were
heaved up, the vallies, which now hold the sea, were formed by the
earth
subsiding into the cavities made by the rising mountains; as the
steam,
which raised them condensed; which would thence not have any
caverns of
great extent remain beneath them, as some philosophers have
imagined.
The earthquakes of modern days are of very small extent indeed
compared
to those of antient times, and are ingeniously compared by M. De
Luc to
the operations of a mole-hill, where from a small cavity are raised
from
time to time small quantities of lava or pumice stone. Monthly
Review,
June, 1790.]
[The moon's refulgent car. l. 79. See additional notes, No.
XV. on
solar volcanos.]
[Her airless realms of frost. l. 82. If the moon had no
atmosphere at
the time of its elevation from the earth; or if its atmosphere was
afterwards stolen from it by the earth's attraction; the water on
the
moon would rise quickly into vapour; and the cold produced by a
certain
quantity of this evaporation would congeal the remainder of it.
Hence it
is not probable that the moon is at present inhabited, but as it
seems
to have suffered and to continue to suffer much by volcanos, a
sufficient quantity of air may in process of time be generated to
produce an atmosphere; which may prevent its heat from so easily
escaping, and its water from so easily evaporating, and thence
become
fit for the production of vegetables and animals.
That the moon possesses little or no atmosphere is deduced from the
undiminished lustre of the stars, at the instant when they emerge
from
behind her disk. That the ocean of the moon is frozen, is confirmed
from
there being no appearance of lunar tides; which, if they existed,
would
cover the part of her disk nearest the earth. See note on Canto
III. l.
61.]
“GNOMES! how you trembled! with the dreadful force
When Earth recoiling stagger'd from her course;
85 When, as her Line in slower circles spun,
And her shock'd axis nodded from the sun,
With dreadful march the accumulated main
Swept her vast wrecks of mountain, vale, and plain;
And, while new tides their shouting floods unite,
90 And hail their Queen, fair Regent of the night;
Chain'd to one centre whirl'd the kindred spheres,
And mark'd with lunar cycles solar years.
[When earth recoiling. l. 84. On supposition that the moon
was thrown
from the earth by the explosion of water or the generation of other
vapours of greater power, the remaining part of the globe would
recede
from its orbit in one direction as the moon receded in another, and
that
in proportion to the respective momentum of each, and would
afterwards
revolve round their common centre of gravity.
If the moon rose from any part of the earth except exactly at the
line
or poles, the shock would tend to turn the axis of the earth out of
its
previous direction. And as a mass of matter rising from deep parts
of
the globe would have previously acquired less diurnal velocity than
the
earth's surface from whence it rose, it would receive during the
time of
its rising additional velocity from the earth's surface, and would
consequently so much retard the motion of the earth round its axis.
When the earth thus receded the shock would overturn all its
buildings
and forests, and the water would rush with inconceivable violence
over
its surface towards the new satellite, from two causes, both by its
not
at first acquiring the velocity with which the earth receded, and
by the
attraction of the new moon, as it leaves the earth; on these
accounts at
first there would be but one tide till the moon receded to a
greater
distance, and the earth moving round a common centre of gravity
between
them, the water on the side furthest from the moon would acquire a
centrifugal force in respect to this common centre between itself
and
the moon.]
IV. “GNOMES! you then bade dissolving SHELLS distil
From the loose summits of each shatter'd hill,
95 To each fine pore and dark interstice flow,
And fill with liquid chalk the mass below.
Whence sparry forms in dusky caverns gleam
With borrow'd light, and twice refract the beam;
While in white beds congealing rocks beneath
100 Court the nice chissel, and desire to breathe.—
[Footnote: Dissolving shells distil. l. 93. The lime-stone
rocks have
had their origin from shells formed beneath the sea, the softer
strata
gradually dissolving and filling up the interstices of the harder
ones,
afterwards when these accumulations of shells were elevated above
the
waters the upper strata became dissolved by the actions of the air
and
dews, and filled up the interstices beneath, producing solid rocks
of
different kinds from the coarse lime-stones to the finest marbles.
When
those lime-stones have been in such a situation that they could
form
perfect crystals they are called spars, some of which possess a
double
refraction, as observed by Sir Isaac Newton. When these crystals
are
jumbled together or mixed with some colouring impurities it is
termed
marble, if its texture be equable and firm; if its texture be
coarse and
porous yet hard, it is called lime-stone; if its texture be very
loose
and porous it is termed chalk. In some rocks the shells remain
almost
unchanged and only covered, or bedded with lime-stone, which seems
to
have been dissolved and sunk down amongst them. In others the
softer
shells and bones are dissolved, and only sharks teeth or harder
echini
have preserved their form inveloped in the chalk or lime-stone; in
some
marbles the solution has been compleat and no vestiges of shell
appear,
as in the white kind called statuary by the workmen. See addit.
notes,
No. XVI.]
“Hence wearied HERCULES in marble rears
His languid limbs, and rests a thousand years;
Still, as he leans, shall young ANTINOUS please
With careless grace, and unaffected ease;
105 Onward with loftier step APOLLO spring,
And launch the unerring arrow from the string;
In Beauty's bashful form, the veil unfurl'd,
Ideal VENUS win the gazing world.
Hence on ROUBILIAC'S tomb shall Fame sublime
110 Wave her triumphant wings, and conquer Time;
Long with soft touch shall DAMER'S chissel charm,
With grace delight us, and with beauty warm;
FOSTER'S fine form shall hearts unborn engage,
And MELBOURN's smile enchant another age.
[Hence wearied Hercules. l. 101. Alluding to the celebrated
Hercules
of Glyco resting after his labours; and to the easy attitude of
Antinous; the lofty step of the Apollo of Belvidere; and the
retreating
modesty of the Venus de Medici. Many of the designs by Roubiliac in
Westminster Abbey are uncommonly poetical; the allegory of Time and
Fame
contending for the trophy of General Wade, which is here alluded
to, is
beautifully told; the wings of Fame are still expanded, and her
hair
still floating in the air; which not only shews that she has that
moment
arrived, but also that her force is not yet expended; at the same
time,
that the old figure of Time with his disordered wings is rather
leaning
backwards and yielding to her impulse, and must apparently in
another
instant be driven from his attack upon the trophy.]
[Foster's fine form. l. 113. Alluding to the beautiful
statues of Lady
Elizabeth Foster and of Lady Melbourn executed by the ingenious
Mrs.
Damer.]
115 V. GNOMES! you then taught transuding dews to pass
Through time-fall'n woods, and root-inwove morass
Age after age; and with filtration fine
Dispart, from earths and sulphurs, the saline.
[Root-inwove morass. l. 116. The great mass of matter which
rests upon
the lime-stone strata of the earth, or upon the granite where the
lime-
stone stratum has been removed by earthquakes or covered by lava,
has
had its origin from the recrements of vegetables and of
air-breathing
animals, as the lime-stone had its origin from sea animals. The
whole
habitable world was originally covered with woods, till mankind
formed
themselves into societies, and subdued them by fire and by steel.
Hence
woods in uncultivated countries have grown and fallen through many
ages,
whence morasses of immense extent; and from these as the more
soluble
parts were washed away first, were produced sea-salt, nitre, iron,
and
variety of acids, which combining with calcareous matter were
productive
of many fossil bodies, as flint, sea-sand, selenite, with the
precious
stones, and perhaps the diamond. See additional notes, No. XVII.]
1. “HENCE with diffusive SALT old Ocean steeps
120 His emerald shallows, and his sapphire deeps.
Oft in wide lakes, around their warmer brim
In hollow pyramids the crystals swim;
Or, fused by earth-born fires, in cubic blocks
Shoot their white forms, and harden into rocks.
[Hence with diffusive salt. l. 119. Salts of various kinds
are
produced from the recrements of animal and vegetable bodies, such
as
phosphoric, ammoniacal, marine salt, and others; these are washed
from
the earth by rains, and carried down our rivers into the sea; they
seem
all here to decompose each other except the marine salt, which has
therefore from the beginning of the habitable world been
perpetually
accumulating.
There is a town in the immense salt-mines of Cracow in Poland, with
a
market-place, a river, a church, and a famous statue, (here
supposed to
be of Lot's wife) by the moist or dry appearance of which the
subterranean inhabitants are said to know when the weather is fair
above
ground. The galleries in these mines are so numerous and so
intricate,
that workmen have frequently lost their way, their lights having
been
burnt out, and have perished before they could be found. Essais,
&c. par
M. Macquart. And though the arches of these different stories of
galleries are boldly executed, yet they are not dangerous; as they
are
held together or supported by large masses of timber of a foot
square;
and these vast timbers remain perfectly sound for many centuries,
while
all other pillars whether of brick, cement, or salt soon dissolve
or
moulder away. Ibid. Could the timbers over water-mill wheels or
cellars,
be thus preserved by occasionally soaking them with brine? These
immense
masses of rock-salt seem to have been produced by the evaporation
of
sea-water in the early periods of the world by subterranean fires.
Dr.
Hutton's Theory of the Earth. See also Theorie des Sources Salees,
par
Mr. Struve. Histoire de Sciences de Lausanne. Tom. II. This idea of
Dr.
Hutton's is confirmed by a fact mentioned in M. Macquart's Essais
sur
Minerologie, who found a great quantity of fossil shells,
principally
bi-valves and madre-pores, in the salt-mines of Wialiczka near
Cracow.
During the evaporation of the lakes of salt-water, as in artificial
salt-works, the salt begins to crystallize near the edges where the
water is shallowest, forming hollow inverted pyramids; which, when
they
become of a certain size, subside by their gravity; if urged by a
stronger fire the salt fuses or forms large cubes; whence the salt
shaped in hollow pyramids, called flake-salt, is better tasted and
preserves flesh better, than the basket or powder salt; because it
is
made by less heat and thence contains more of the marine acid. The
sea-
water about our island contains from about one twenty-eighth to one
thirtieth part of sea-salt, and about one eightieth of magnesian
salt.
See Brownrigg on Salt. See note on Ocymum, Vol. II. of this work.]
125 “Thus, cavern'd round in CRACOW'S mighty mines,
With crystal walls a gorgeous city shines;
Scoop'd in the briny rock long streets extend
Their hoary course, and glittering domes ascend;
Down the bright steeps, emerging into day,
130 Impetuous fountains burst their headlong way,
O'er milk-white vales in ivory channels spread,
And wondering seek their subterraneous bed.
Form'd in pellucid salt with chissel nice,
The pale lamp glimmering through the sculptured ice,
135 With wild reverted eyes fair LOTTA stands,
And spreads to Heaven, in vain, her glassy hands;
Cold dews condense upon her pearly breast,
And the big tear rolls lucid down her vest.
Far gleaming o'er the town transparent fanes
140 Rear their white towers, and wave their golden vanes;
Long lines of lustres pour their trembling rays,
And the bright vault returns the mingled blaze.
2. “HENCE orient NITRE owes it's sparkling birth,
And with prismatic crystals gems the earth,
145 O'er tottering domes in filmy foliage crawls,
Or frosts with branching plumes the mouldering walls.
As woos Azotic Gas the virgin Air,
And veils in crimson clouds the yielding Fair,
Indignant Fire the treacherous courtship flies,
150 Waves his light wing, and mingles with the skies.
[Hence orient Nitre. l. 143. Nitre is found in Bengal
naturally
crystallized, and is swept by brooms from earths and stones, and
thence
called sweepings of nitre. It has lately been found in large
quantities
in a natural bason of calcareous earth at Molfetta in Italy, both
in
thin strata between the calcareous beds, and in efflorescences of
various beautiful leafy and hairy forms. An account of this
nitre-bed is
given by Mr. Zimmerman and abridged in Rozier's Journal de Physique
Fevrier. 1790. This acid appears to be produced in all situations
where
animal and vegetable matters are compleatly decomposed, and which
are
exposed to the action of the air as on the walls of stables, and
slaughter-houses; the crystals are prisms furrowed by longitudinal
groves.
Dr. Priestley discovered that nitrous air or gas which he obtained
by
dissolving metals in nitrous acid, would combine rapidly with vital
air,
and produce with it a true nitrous acid; forming red clouds during
the
combination; the two airs occupy only the space before occupied by
one
of them, and at the same time heat is given out from the new
combination. This dimunition of the bulk of a mixture of nitrous
gas and
vital air, Dr. Priestley ingeniously used as a test of the purity
of the
latter; a discovery of the greatest importance in the analysis of
airs.
Mr. Cavendish has since demonstrated that two parts of vital air or
oxygene, and one part of phlogistic air or azote, being long
exposed to
electric shocks, unite, and produce nitrous acid. Philos. Trans.
Vols.
LXXV. and LXXVIII.
Azote is one of the most abundant elements in nature, and combined
with
calorique or heat, it forms azotic gas or phlogistic air, and
composes
two thirds of the atmosphere; and is one of the principal component
parts of animal bodies, and when united to vital air or oxygene
produces
the nitrous acid. Mr. Lavoisier found that 211/2 parts by weight of
azote, and 431/2 parts of oxygene produced 64 parts of nitrous gas,
and
by the further addition of 36 parts of oxygene nitrous acid was
produced. Traite de Chimie. When two airs become united so as to
produce
an unelastic liquid much calorique or heat is of necessity expelled
from
the new combination, though perhaps nitrous acid and oxygenated
marine
acid admit more heat into their combinations than other acids.]
“So Beauty's GODDESS, warm with new desire,
Left, on her silver wheels, the GOD of Fire;
Her faithless charms to fiercer MARS resign'd,
Met with fond lips, with wanton arms intwin'd.
155 —Indignant VULCAN eyed the parting Fair,
And watch'd with jealous step the guilty pair;
O'er his broad neck a wiry net he flung,
Quick as he strode, the tinkling meshes rung;
Fine as the spider's flimsy thread He wove
160 The immortal toil to lime illicit love;
Steel were the knots, and steel the twisted thong,
Ring link'd in ring, indissolubly strong;
On viewless hooks along the fretted roof
He hung, unseen, the inextricable woof.—
165 —Quick start the springs, the webs pellucid spread,
And lock the embracing Lovers on their bed;
Fierce with loud taunts vindictive VULCAN springs,
Tries all the bolts, and tightens all the strings,
Shakes with incessant shouts the bright abodes,
170 Claps his rude hands, and calls the festive Gods.—
—With spreading palms the alarmed Goddess tries
To veil her beauties from celestial eyes,
Writhes her fair limbs, the slender ringlets strains,
And bids her Loves untie the obdurate chains;
175 Soft swells her panting bosom, as she turns,
And her flush'd cheek with brighter blushes burns.
Majestic grief the Queen of Heaven avows,
And chaste Minerva hides her helmed brows;
Attendant Nymphs with bashful eyes askance
180 Steal of intangled MARS a transient glance;
Surrounding Gods the circling nectar quaff,
Gaze on the Fair, and envy as they laugh.
3. “HENCE dusky IRON sleeps in dark abodes,
And ferny foliage nestles in the nodes;
185 Till with wide lungs the panting bellows blow,
And waked by fire the glittering torrents flow;
—Quick whirls the wheel, the ponderous hammer falls,
Loud anvils ring amid the trembling walls,
Strokes follow strokes, the sparkling ingot shines,
190 Flows the red slag, the lengthening bar refines;
Cold waves, immersed, the glowing mass congeal,
And turn to adamant the hissing Steel.
[Hence dusky Iron. l. 183. The production of iron from the
decomposition of vegetable bodies is perpetually presented to our
view;
the waters oozing from all morasses are chalybeate, and deposit
their
ochre on being exposed to the air, the iron acquiring a calciform
state
from its union with oxygene or vital air. Where thin morasses lie
on
beds of gravel the latter are generally stained by the filtration
of
some of the chalybeate water through them. This formation of iron
from
vegetable recrements is further evinced by the fern leaves and
other
parts of vegetables, so frequently found in the centre of the knobs
or
nodules of some iron-ores.
In some of these nodules there is a nucleus of whiter iron-earth
surrounded by many concentric strata of darker and lighter
iron-earth
alternately. In one, which now lies before me, the nucleus is a
prism of
a triangular form with blunted angles, and about half an inch high,
and
an inch and half broad; on every side of this are concentric strata
of
similar iron-earth alternately browner and less brown; each stratum
is
about a tenth of an inch in thickness and there are ten of them in
number. To what known cause can this exactly regular distribution
of so
many earthy strata of different colours surrounding the nucleus be
ascribed? I don't know that any mineralogists have attempted an
explanation of this wonderful phenomenon. I suspect it is owing to
the
polarity of the central nucleus. If iron-filings be regularly laid
on
paper by means of a small sieve, and a magnet be placed underneath,
the
filings will dispose themselves in concentric curves with vacant
intervals between them. Now if these iron-filings are conceived to
be
suspended in a fluid, whose specific gravity is similar to their
own,
and a magnetic bar was introduced as an axis into this fluid, it is
easy
to foresee that the iron filings would dispose themselves into
concentric spheres, with intervals of the circumnatant fluid
between
them, exactly as is seen in these nodules of iron-earth. As all the
lavas consist of one fourth of iron, (Kirvan's Mineral) and almost
all
other known bodies, whether of animal or vegetable origin, possess
more
or less of this property, may not the distribution of a great
portion of
the globe of the earth into strata of greater or less regularity be
owing to the polarity of the whole?]
[And turn to adamant. l. 192. The circumstances which render
iron more
valuable to mankind than any other metal are, 1. its property of
being
rendered hard to so great a degree and thus constituting such
excellent
tools. It was the discovery of this property of iron, Mr. Locke
thinks,
that gave such pre-eminence to the European world over the American
one.
2. Its power of being welded; that is, when two pieces are made
very hot
and applied together by hammering, they unite compleatly, unless
any
scale of iron intervenes; and to prevent this it is usual for
smiths to
dip the very hot bar in sand, a little of which fuses into fluid
glass
with the scale and is squeezed out from between the uniting parts
by the
force of hammering. 3. Its power of acquiring magnetism.
It is however to be wished that gold or silver were discovered in
as
great quantity as iron, since these metals being indestructible by
exposure to air, water, fire or any common acids would supply
wholesome
vessels for cookery, so much to be desired, and so difficult to
obtain,
and would form the most light and durable coverings for houses, as
well
as indestructible fire-grates, ovens, and boiling vessels. See
additional notes, No. XVIII. on Steel.]
“Last MICHELL'S hands with touch of potent charm
The polish'd rods with powers magnetic arm;
195 With points directed to the polar stars
In one long line extend the temper'd bars;
Then thrice and thrice with steady eye he guides,
And o'er the adhesive train the magnet slides;
The obedient Steel with living instinct moves,
200 And veers for ever to the pole it loves.
[Last Michell's hands. l. 193. The discovery of the magnet
seems to
have been in very early times; it is mentioned by Plato, Lucretius,
Pliny, and Galen, and is said to have taken its name of magnes from
Magnesia, a sea-port of antient Lybia.
As every piece of iron which was made magnetical by the touch of a
magnet became itself a magnet, many attempts were made to improve
these
artificial magnets, but without much success till Servingdon
Savary,
Esq. made them of hardened steel bars, which were so powerful that
one
of them weighing three pounds averdupois would lift another of the
same
weight. Philos. Trans.
After this Dr. Knight made very successful experiments on this
subject,
which, though he kept his method secret, seems to have excited
others to
turn their attention to magnetism. At this time the Rev. Mr.
Michell
invented an equally efficacious and more expeditious way of making
strong artificial magnets, which he published in the end of the
year
1750, in which he explained his method of what he called “the
double
touch", and which, since Mr. Knight's method has been known,
appears to
be somewhat different from it.
This method of rendering bars of hardened steel magnetical consists
in
holding vertically two or more magnetic bars nearly parallel to
each
other with their opposite poles very near each other (but
nevertheless
separated to a small distance), these are to be slided over a line
of
bars laid horizontally a few times backward and forward. See
Michell on
Magnetism, also a detailed account in Chamber's Dictionary.
What Mr. Michell proposed by this method was to include a very
small
portion of the horizontal bars, intended to be made magnetical,
between
the joint forces of two or more bars already magnetical, and by
sliding
them from end to end every part of the line of bars became
successively
included, and thus bars possessed of a very small degree of
magnetism to
begin with, would in a few times sliding backwards and forwards
make the
other ones much more magnetical than themselves, which are then to
be
taken up and used to touch the former, which are in succession to
be
laid down horizontally in a line.
There is still a great field remains for future discoveries in
magnetism
both in respect to experiment and theory; the latter consists of
vague
conjectures the more probable of which are perhaps those of
Elpinus, as
they assimulate it to electricity.
One conjecture I shall add, viz. that the polarity of magnetism may
be
owing to the earth's rotatory motion. If heat, electricity, and
magnetism are supposed to be fluids of different gravities, heat
being
the heaviest of them, electricity the next heavy, and magnetism the
lightest, it is evident that by the quick revolution of the earth
the
heat will be accumulated most over the line, electricity next
beneath
this, and that the magnetism will be detruded to the poles and axis
of
the earth, like the atmospheres of common air and of inflammable
gas, as
explained in the note on Canto I. l. 123.
Electricity and heat will both of them displace magnetism, and this
shows that they may gravitate on each other; and hence when too
great a
quantity of the electric fluid becomes accumulated at the poles by
descending snows, or other unknown causes, it may have a tendency
to
rise towards the tropics by its centrifugal force, and produce the
northern lights. See additional notes, No. I.]
“Hail, adamantine STEEL! magnetic Lord!
King of the prow, the plowshare, and the sword!
True to the pole, by thee the pilot guides
His steady helm amid the struggling tides,
205 Braves with broad sail the immeasurable sea,
Cleaves the dark air, and asks no star but Thee.—
By thee the plowshare rends the matted plain,
Inhumes in level rows the living grain;
Intrusive forests quit the cultured ground,
210 And Ceres laughs with golden fillets crown'd.—
O'er restless realms when scowling Discord flings
Her snakes, and loud the din of battle rings;
Expiring Strength, and vanquish'd Courage feel
Thy arm resistless, adamantine STEEL!
215 4. “HENCE in fine streams diffusive ACIDS flow,
Or wing'd with fire o'er Earth's fair bosom blow;
Transmute to glittering Flints her chalky lands,
Or sink on Ocean's bed in countless Sands.
Hence silvery Selenite her chrystal moulds,
220 And soft Asbestus smooths his silky folds;
His cubic forms phosphoric Fluor prints,
Or rays in spheres his amethystine tints.
Soft cobweb clouds transparent Onyx spreads,
And playful Agates weave their colour'd threads;
225 Gay pictured Mochoes glow with landscape-dyes,
And changeful Opals roll their lucid eyes;
Blue lambent light around the Sapphire plays,
Bright Rubies blush, and living Diamonds blaze.
[Diffusive Acids flow. l. 215. The production of marine acid
from
decomposing vegetable and animal matters with vital air, and of
nitrous
acid from azote and vital air, the former of which is united to its
basis by means of the exhalations from vegetable and animal
matters,
constitute an analogy which induces us to believe that many other
acids
have either their bases or are united to vital air by means of some
part
of decomposing vegetable and animal matters.
The great quantities of flint sand whether formed in mountains or
in the
sea would appear to derive its acid from the new world, as it is
found
above the strata of lime-stone and granite which constitute the old
world, and as the earthy basis of flint is probably calcareous, a
great
part of it seems to be produced by a conjunction of the new and old
world; the recrements of air-breathing animals and vegetables
probably
afford the acid, and the shells of marine animals the earthy basis,
while another part may have derived its calcareous part also from
the
decomposition of vegetable and animal bodies.
The same mode of reasoning seems applicable to the siliceous stones
under various names, as amethyst, onyx, agate, mochoe, opal, &c.
which
do not seem to have undergone any process from volcanic fires, and
as
these stones only differ from flint by a greater or less admixture
of
argillaceous and calcareous earths. The different proportions of
which
in each kind of stone may be seen in Mr. Kirwan's valuable Elements
of
Mineralogy. See additional notes, No. XIX.]
[Living diamonds blaze. l. 228. Sir Isaac Newton having
observed the
great power of refracting light, which the diamond possesses above
all
other crystallized or vitreous matter, conjectured that it was an
inflammable body in some manner congealed. Insomuch that all the
light
is reflected which falls on any of its interior surfaces at a
greater
angle of incidence than 241/2 degrees; whereas an artificial gem of
glass does not reflect any light from its hinder surface, unless
that
surface is inclined in an angle of 41 degrees. Hence the diamond
reflects half as much more light as a factitious gem in similar
circumstances; to which must be added its great transparency, and
the
excellent polish it is capable of. The diamond had nevertheless
been
placed at the head of crystals or precious stones by the
mineralogists,
till Bergman ranged it of late in the combustible class of bodies,
because by the focus of Villette's burning mirror it was evaporated
by a
heat not much greater than will melt silver, and gave out light.
Mr.
Hoepfner however thinks the dispersion of the diamond by this great
heat
should be called a phosphorescent evaporation of it, rather than a
combustion; and from its other analogies of crystallization,
hardness,
transparency, and place of its nativity, wishes again to replace it
amongst the precious stones. Observ. sur la Physique, par Rozier,
Tom.
XXXV. p. 448. See new edition of the Translation of Cronsted, by De
Costa.]
“Thus, for attractive earth, inconstant JOVE
230 Mask'd in new shapes forsook his realms above.—
First her sweet eyes his Eagle-form beguiles,
And HEBE feeds him with ambrosial smiles;
Next the chang'd God a Cygnet's down assumes,
And playful LEDA smooths his glossy plumes;
235 Then glides a silver Serpent, treacherous guest!
And fair OLYMPIA folds him in her breast;
Now lows a milk-white Bull on Afric's strand,
And crops with dancing head the daisy'd land.—
With rosy wreathes EUROPA'S hand adorns
240 His fringed forehead, and his pearly horns;
Light on his back the sportive Damsel bounds,
And pleased he moves along the flowery grounds;
Bears with slow step his beauteous prize aloof,
Dips in the lucid flood his ivory hoof;
245 Then wets his velvet knees, and wading laves
His silky sides amid the dimpling waves.
While her fond train with beckoning hands deplore,
Strain their blue eyes, and shriek along the shore;
Beneath her robe she draws her snowy feet,
250 And, half-reclining on her ermine seat,
Round his raised neck her radiant arms she throws,
And rests her fair cheek on his curled brows;
Her yellow tresses wave on wanton gales,
And high in air her azure mantle sails.
255 —Onward He moves, applauding Cupids guide,
And skim on shooting wing the shining tide;
Emerging Triton's leave their coral caves,
Sound their loud conchs, and smooth the circling waves,
Surround the timorous Beauty, as she swims,
260 And gaze enamour'd on her silver limbs.
—Now Europe's shadowy shores with loud acclaim
Hail the fair fugitive, and shout her name;
Soft echoes warble, whispering forests nod,
And conscious Nature owns the present God.
265 —Changed from the Bull, the rapturous God assumes
Immortal youth, with glow celestial blooms,
With lenient words her virgin fears disarms,
And clasps the yielding Beauty in his arms;
Whence Kings and Heroes own illustrious birth,
270 Guards of mankind, and demigods on earth.
[Inconstant Jove. l. 229. The purer air or ether in the
antient
mythology was represented by Jupiter, and the inferior air by Juno;
and
the conjunction of these deities was said to produce the vernal
showers,
and procreate all things, as is further spoken of in Canto III. l.
204.
It is now discovered that pure air, or oxygene, uniting with
variety of
bases forms the various kinds of acids; as the vitriolic acid from
pure
air and sulphur; the nitrous acid from pure air and phlogistic air,
or
azote; and carbonic acid, (or fixed air,) from pure air and
charcoal.
Some of these affinities were perhaps portrayed by the Magi of
Egypt,
who were probably learned in chemistry, in their hieroglyphic
pictures
before the invention of letters, by the loves of Jupiter with
terrestrial ladies. And thus physically as well as metaphysically
might
be said “Jovis omnia plena.”]
VI. “GNOMES! as you pass'd beneath the labouring soil,
The guards and guides of Nature's chemic toil,
YOU saw, deep-sepulchred in dusky realms,
Which Earth's rock-ribbed ponderous vault o'erwhelms,
275 With self-born fires the mass fermenting glow,
And flame-wing'd sulphurs quit the earths below.
[With self-born fires. l. 275. After the accumulation of
plains and
mountains on the calcareous rocks or granite which had been
previously
raised by volcanic fires, a second set of volcanic fires were
produced
by the fermentation of this new mass, by which after the salts or
acids
and iron had been washed away in part by elutriation, dissipated
the
sulphurous parts which were insoluble in water; whence argillaceous
and
siliceous earths were left in some places; in others, bitumen
became
sublimed to the upper part of the stratum, producing coals of
various
degrees of purity.]
1. “HENCE ductile CLAYS in wide expansion spread,
Soft as the Cygnet's down, their snow-white bed;
With yielding flakes successive forms reveal,
280 And change obedient to the whirling wheel.
—First CHINA'S sons, with early art elate,
Form'd the gay tea-pot, and the pictured plate;
Saw with illumin'd brow and dazzled eyes
In the red stove vitrescent colours rise;
285 Speck'd her tall beakers with enamel'd stars,
Her monster-josses, and gigantic jars;
Smear'd her huge dragons with metallic hues,
With golden purples, and cobaltic blues;
Bade on wide hills her porcelain castles glare,
290 And glazed Pagodas tremble in the air.
[Hence ductile clays l. 277. See additional notes, No. XX.]
[Saw with illumin'd brow. l. 283. No colour is
distinguishable in the
red-hot kiln but the red itself, till the workman introduces a
small
piece of dry wood, which by producing a white flame renders all the
other colours visible in a moment.]
[With golden purples. l. 288. See additional notes, No.
XXI.]
“ETRURIA! next beneath thy magic hands
Glides the quick wheel, the plaistic clay expands,
Nerved with fine touch, thy fingers (as it turns)
Mark the nice bounds of vases, ewers, and urns;
295 Round each fair form in lines immortal trace
Uncopied Beauty, and ideal Grace.
[Etruria! next. l. 291. Etruria may perhaps vie with China
itself in
the antiquity of its arts. The times of its greatest splendour were
prior to the foundations of Rome, and the reign of one of its best
princes, Janus, was the oldest epoch the Romans knew. The earliest
historians speak of the Etruscans as being then of high antiquity,
most
probably a colony from Phoenicia, to which a Pelasgian colony
acceded,
and was united soon after Deucalion's flood. The peculiar character
of
their earthern vases consists in the admirable beauty, simplicity,
and
diversity of forms, which continue the best models of taste to the
artists of the present times; and in a species of non-vitreous
encaustic
painting, which was reckoned, even in the time of Pliny, among the
lost
arts of antiquity, but which has lately been recovered by the
ingenuity
and industry of Mr. Wedgwood. It is supposed that the principal
manufactories were about Nola, at the foot of Vesuvius; for it is
in
that neighbourhood that the greatest quantities of antique vases
have
been found; and it is said that the general taste of the
inhabitants is
apparently influenced by them; insomuch that strangers coming to
Naples,
are commonly struck with the diversity and elegance even of the
most
ordinary vases for common uses. See D'Hancarville's preliminary
discourses to the magnificent collection of Etruscan vases,
published by
Sir William Hamilton.]
“GNOMES! as you now dissect with hammers fine
The granite-rock, the nodul'd flint calcine;
Grind with strong arm, the circling chertz betwixt,
300 Your pure Ka-o-lins and Pe-tun-tses mixt;
O'er each red saggars burning cave preside,
The keen-eyed Fire-Nymphs blazing by your side;
And pleased on WEDGWOOD ray your partial smile,
A new Etruria decks Britannia's isle.—
305 Charm'd by your touch, the flint liquescent pours
Through finer sieves, and falls in whiter showers;
Charm'd by your touch, the kneaded clay refines,
The biscuit hardens, the enamel shines;
Each nicer mould a softer feature drinks,
310 The bold Cameo speaks, the soft Intaglio thinks.
[Illustration: H. Webber init J. Holloway sculpt Copied from
Capt.
Phillip's Voyage to Botany Bay, by permission of the Proprietor
]
[Transcriber's note: names of painter and engraver are only
guesswork.]
[Illustration: AM I NOT A MAN AND A BROTHER]
“To call the pearly drops from Pity's eye,
Or stay Despair's disanimating sigh,
Whether, O Friend of art! the gem you mould
Rich with new taste, with antient virtue bold;
315 Form the poor fetter'd SLAVE on bended knee
From Britain's sons imploring to be free;
Or with fair HOPE the brightening scenes improve,
And cheer the dreary wastes at Sydney-cove;
Or bid Mortality rejoice and mourn
320 O'er the fine forms on PORTLAND'S mystic urn.—
[Form the poor fetter'd Slave. l. 315. Alluding to two
cameos of Mr.
Wedgwood's manufacture; one of a Slave in chains, of which he
distributed many hundreds, to excite the humane to attend to and to
assist in the abolition of the detestable traffic in human
creatures;
and the other a cameo of Hope attended by Peace, and Art, and
Labour;
which was made of clay from Botany Bay; to which place he sent many
of
them to shew the inhabitants what their materials would do, and to
encourage their industry. A print of this latter medallion is
prefixed
to Mr. Stockdale's edition of Philip's Expedition to Botany Bay.]
[Portland's mystic urn. l. 320. See additional notes, No.
XXII.]
“Here by fall'n columns and disjoin'd arcades,
On mouldering stones, beneath deciduous shades,
Sits HUMANKIND in hieroglyphic state,
Serious, and pondering on their changeful state;
325 While with inverted torch, and swimming eyes,
Sinks the fair shade of MORTAL LIFE, and dies.
There the pale GHOST through Death's wide portal bends
His timid feet, the dusky steep descends;
With smiles assuasive LOVE DIVINE invites,
330 Guides on broad wing, with torch uplifted lights;
IMMORTAL LIFE, her hand extending, courts
The lingering form, his tottering step supports;
Leads on to Pluto's realms the dreary way,
And gives him trembling to Elysian day.
335 Beneath in sacred robes the PRIESTESS dress'd,
The coif close-hooded, and the fluttering vest,
With pointing finger guides the initiate youth,
Unweaves the many-colour'd veil of Truth,
Drives the profane from Mystery's bolted door,
340 And Silence guards the Eleusinian lore.—
[Illustration: The Portland Vase]
[Illustration: The first Compartment, London Published Dec'r
1st 1791
by J. Johnson, St. Paul's Church Yard.]
[Transcriber's note: 2nd line with date very small and nearly
illegible]
[Illustration: The second Compartment]
[Illustration: The Handles &Bottom of the Vase. London
Published
Dec'r 1st 1791 by J. Johnson, St. Paul's Church Yard.]
“Whether, O Friend of Art! your gems derive
Fine forms from Greece, and fabled Gods revive;
Or bid from modern life the Portrait breathe,
And bind round Honour's brow the laurel wreath;
345 Buoyant shall sail, with Fame's historic page,
Each fair medallion o'er the wrecks of age;
Nor Time shall mar; nor steel, nor fire, nor rust
Touch the hard polish of the immortal bust.
[Fine forms from Greece. l. 342. In real stones, or in paste
or soft
coloured glass, many pieces of exquisite workmanship were produced
by
the antients. Basso-relievos of various sizes were made in coarse
brown
earth of one colour; but of the improved kind of two or more
colours,
and of a true porcelain texture, none were made by the antients,
nor
attempted I believe by the moderns, before those of Mr. Wedgwood's
manufactory.]
2. “HENCE sable COAL his massy couch extends,
350 And stars of gold the sparkling Pyrite blends;
Hence dull-eyed Naphtha pours his pitchy streams,
And Jet uncolour'd drinks the solar beams,
Bright Amber shines on his electric throne,
And adds ethereal lustres to his own.
355 —Led by the phosphor-light, with daring tread
Immortal FRANKLIN sought the fiery bed;
Where, nursed in night, incumbent Tempest shrouds
The seeds of Thunder in circumfluent clouds,
Besieged with iron points his airy cell,
360 And pierced the monster slumbering in the shell.
[Hence sable Coal. l. 349. See additional notes, No. XXIII.
on coal.]
[Bright Amber shines. l. 353. Coal has probably all been
sublimed more
or less from the clay, with which it was at first formed in
decomposing
morasses; the petroleum seems to have been separated and condensed
again
in superior strata, and a still finer kind of oil, as naphtha, has
probably had the same origin. Some of these liquid oils have again
lost
their more volatile parts, and become cannel-coal, asphaltum, jet,
and
amber, according to the purity of the original fossil oil. Dr.
Priestley
has shewn, that essential oils long exposed to the atmosphere
absorb
both the vital and phlogistic part of it; whence it is probable
their
becoming solid may in great measure depend, as well as by the
exhalation
of their more volatile parts. On distillation with volatile alcaly
all
these fossil oils are shewn to contain the acid of amber, which
evinces
the identity of their origin. If a piece of amber be rubbed it
attracts
straws and hairs, whence the discovery of electricity, and whence
its
name, from electron the Greek word for amber.]
[Immortal Franklin. l. 356. See note on Canto I. l. 383.]
“So, born on sounding pinions to the WEST,
When Tyrant-Power had built his eagle nest;
While from his eyry shriek'd the famish'd brood,
Clenched their sharp claws, and champ'd their beaks for blood,
365 Immortal FRANKLIN watch'd the callow crew,
And stabb'd the struggling Vampires, ere they flew.
—The patriot-flame with quick contagion ran,
Hill lighted hill, and man electrised man;
Her heroes slain awhile COLUMBIA mourn'd,
370 And crown'd with laurels LIBERTY return'd.
“The Warrior, LIBERTY, with bending sails
Helm'd his bold course to fair HIBERNIA'S vales;—
Firm as he steps, along the shouting lands,
Lo! Truth and Virtue range their radiant bands;
375 Sad Superstition wails her empire torn,
Art plies his oar, and Commerce pours her horn.
“Long had the Giant-form on GALLIA'S plains
Inglorious slept, unconscious of his chains;
Round his large limbs were wound a thousand strings
380 By the weak hands of Confessors and Kings;
O'er his closed eyes a triple veil was bound,
And steely rivets lock'd him to the ground;
While stern Bastile with iron cage inthralls
His folded limbs, and hems in marble walls.
385 —Touch'd by the patriot-flame, he rent amazed
The flimsy bonds, and round and round him gazed;
Starts up from earth, above the admiring throng
Lifts his Colossal form, and towers along;
High o'er his foes his hundred arms He rears,
390 Plowshares his swords, and pruning hooks his spears;
Calls to the Good and Brave with voice, that rolls
Like Heaven's own thunder round the echoing poles;
Gives to the winds his banner broad unfurl'd,
And gathers in its shade the living world!
[While stern Bastile. l. 383. “We descended with great
difficulty into
the dungeons, which were made too low for our standing upright; and
were
so dark, that we were obliged at noon-day to visit them by the
light of
a candle. We saw the hooks of those chains, by which the prisoners
were
fastened by their necks to the walls of their cells; many of which
being
below the level of the water were in a constant state of humidity;
from
which issued a noxious vapour, which more than once extinguished
the
candles. Since the destruction of the building many subterraneous
cells
have been discovered under a piece of ground, which seemed only a
bank
of solid earth before the horrid secrets of this prison-house were
disclosed. Some skeletons were found in these recesses with irons
still
fastened to their decayed bones.” Letters from France, by H.M.
Williams,
p. 24.]
395 VII. “GNOMES! YOU then taught volcanic airs to force
Through bubbling Lavas their resistless course,
O'er the broad walls of rifted Granite climb,
And pierce the rent roof of incumbent Lime,
Round sparry caves metallic lustres fling,
400 And bear phlogiston on their tepid wing.
[And pierce the rent roof. l. 398. The granite rocks and the
limestone
rocks have been cracked to very great depths at the time they were
raised up by subterranean fires; in these cracks are found most of
the
metallic ores, except iron and perhaps manganese, the former of
which is
generally found in horizontal strata, and the latter generally near
the
surface of the earth.
Philosophers possessing so convenient a test for the discovery of
iron
by the magnet, have long since found it in all vegetable and animal
matters; and of late Mr. Scheele has discovered the existence of
manganese in vegetable ashes. Scheele, 56 mem. Stock. 1774. Kirwan.
Min.
353. Which accounts for the production of it near the surface of
earth,
and thence for its calciform appearance, or union with vital air.
Bergman has likewise shewn, that the limestones which become bluish
or
dark coloured when calcined, possess a mixture of manganese, and
are
thence preferable as a cement to other kinds of lime. 2. Bergman,
229.
Which impregnation with manganese has probably been received from
the
decomposition of superincumbent vegetable matters.
These cracks or perpendicular caverns in the granite or limestone
pass
to unknown depths; and it is up these channels that I have
endeavoured
to shew that the steam rises which becomes afterwards condensed and
produces the warm springs of this island, and other parts of the
world.
(See note on Fucus, Vol. II.) And up these cracks I suppose certain
vapours arise, which either alone, or by meeting with something
descending into them from above, have produced most of the metals;
and
several of the materials in which they are bedded. Thus the
ponderous
earth, Barytes, of Derbyshire, is found in these cracks, and is
stratified frequently with lead-ore, and frequently surrounds it.
This
ponderous earth has been found by Dr. Hoepfner in a granite in
Switzerland, and may have thus been sublimed from immense depths by
great heat, and have obtained its carbonic or vitriolic acid from
above.
Annales de Chimie. There is also reason to conclude that something
from
above is necessary to the formation of many of the metals: at
Hawkstone
in Shropshire, the seat of Sir Richard Hill, there is an elevated
rock
of siliceous sand which is coloured green with copper in many
places
high in the air; and I have in my possession a specimen of lead
formed
in the cavity of an iron nodule, and another of lead amid spar from
a
crack of a coal-stratum; all which countenance the modern
production of
those metals from descending materials. To which should be added,
that
the highest mountains of granite, which have therefore probably
never
been covered with marine productions on account of their early
elevation, nor with vegetable or animal matters on account of their
great coldness, contain no metallic ores, whilst the lower ones
contain
copper and tin in their cracks or veins, both in Saxony, Silesia,
and
Cornwall. Kirwan's Mineral. p. 374.
The transmutation of one metal into another, though hitherto
undiscovered by the alchymists, does not appear impossible; such
transmutations have been supposed to exist in nature, thus lapis
calaminaris may have been produced from the destruction of
lead-ore, as
it is generally found on the top of the veins of lead, where it has
been
calcined or united with air, and because masses of lead-ore are
often
found intirely inclosed in it. So silver is found mixed in almost
all
lead-ores, and sometimes in seperate filaments within the cavities
of
lead-ore, as I am informed by Mr. Michell, and is thence probably a
partial transmutation of the lead to silver, the rapid progress of
modern chemistry having shewn the analogy between metallic calces
and
acids, may lead to the power of transmuting their bases: a
discovery
much to be wished.]
“HENCE glows, refulgent Tin! thy chrystal grains,
And tawny Copper shoots her azure veins;
Zinc lines his fretted vault with sable ore,
And dull Galena tessellates the floor;
405 On vermil beds in Idria's mighty caves
The living Silver rolls its ponderous waves;
With gay refractions bright Platina shines,
And studs with squander'd stars his dusky mines;
Long threads of netted gold, and silvery darts,
410 Inlay the Lazuli, and pierce the Quartz;—
—Whence roof'd with silver beam'd PERU, of old,
And hapless MEXICO was paved with gold.
“Heavens! on my sight what sanguine colours blaze!
Spain's deathless shame! the crimes of modern days!
415 When Avarice, shrouded in Religion's robe,
Sail'd to the West, and slaughter'd half the globe;
While Superstition, stalking by his side,
Mock'd the loud groans, and lap'd the bloody tide;
For sacred truths announced her frenzied dreams,
420 And turn'd to night the sun's meridian beams.—
Hear, oh, BRITANNIA! potent Queen of isles,
On whom fair Art, and meek Religion smiles,
Now AFRIC'S coasts thy craftier sons invade
With murder, rapine, theft,—and call it Trade!
425 —The SLAVE, in chains, on supplicating knee,
Spreads his wide arms, and lifts his eyes to Thee;
With hunger pale, with wounds and toil oppress'd,
“ARE WE NOT BRETHREN?” sorrow choaks the rest;—
—AIR! bear to heaven upon thy azure flood
430 Their innocent cries!—EARTH! cover not their blood!
VIII. “When Heaven's dread justice smites in crimes
o'ergrown
The blood-nursed Tyrant on his purple throne,
GNOMES! YOUR bold forms unnumber'd arms outstretch,
And urge the vengeance o'er the guilty wretch.—
435 Thus when CAMBYSES led his barbarous hosts
From Persia's rocks to Egypt's trembling coasts,
Defiled each hallowed fane, and sacred wood,
And, drunk with fury, swell'd the Nile with blood;
Waved his proud banner o'er the Theban states,
440 And pour'd destruction through her hundred gates;
In dread divisions march'd the marshal'd bands,
And swarming armies blacken'd all the lands,
By Memphis these to ETHIOP'S sultry plains,
And those to HAMMON'S sand-incircled fanes.—
445 Slow as they pass'd, the indignant temples frown'd,
Low curses muttering from the vaulted ground;
Long ailes of Cypress waved their deepen'd glooms,
And quivering spectres grinn'd amid the tombs;
Prophetic whispers breathed from S
450 And MEMNON'S lyre with hollow murmurs rung;
Burst from each pyramid expiring groans,
And darker shadows stretch'd their lengthen'd cones.—
Day after day their deathful rout They steer,
Lust in the van, and rapine in the rear.
[Thus when Cambyses. l. 435. Cambyses marched one army from
Thebes,
after having overturned the temples, ravaged the country, and
deluged it
with blood, to subdue Ethiopia; this army almost perished by
famine,
insomuch, that they repeatedly slew every tenth man to supply the
remainder with food. He sent another army to plunder the temple of
Jupiter Ammon, which perished overwhelm'd with sand.]
[Expiring groans. l. 451. Mr. Savery or Mr. Volney in their
Travels
through Egypt has given a curious description of one of the
pyramids,
with the operose method of closing them, and immuring the body, (as
they
supposed) for six thousand years. And has endeavoured from thence
to
shew, that, when a monarch died, several of his favourite courtiers
were
inclosed alive with the mummy in these great masses of stone-work;
and
had food and water conveyed to them, as long as they lived, proper
apertures being left for this purpose, and for the admission of
air, and
for the exclusion of any thing offensive.]
455 “GNOMES! as they march'd, You hid the gathered fruits,
The bladed grass, sweet grains, and mealy roots;
Scared the tired quails, that journey'd o'er their heads,
Retain'd the locusts in their earthy beds;
Bade on your sands no night-born dews distil,
460 Stay'd with vindictive hands the scanty rill.—
Loud o'er the camp the Fiend of Famine shrieks,
Calls all her brood, and champs her hundred beaks;
O'er ten square leagues her pennons broad expand,
And twilight swims upon the shuddering sand;
465 Perch'd on her crest the Griffin Discord clings,
And Giant Murder rides between her wings;
Blood from each clotted hair, and horny quill,
And showers of tears in blended streams distil;
High-poised in air her spiry neck she bends,
470 Rolls her keen eye, her Dragon-claws extends,
Darts from above, and tears at each fell swoop
With iron fangs the decimated troop.
“Now o'er their head the whizzing whirlwinds breathe,
And the live desert pants, and heaves beneath;
475 Tinged by the crimson sun, vast columns rise
Of eddying sands, and war amid the skies,
In red arcades the billowy plain surround,
And stalking turrets dance upon the ground.
—Long ranks in vain their shining blades extend,
480 To Demon-Gods their knees unhallow'd bend,
Wheel in wide circle, form in hollow square,
And now they front, and now they fly the war,
Pierce the deaf tempest with lamenting cries,
Press their parch'd lips, and close their blood-shot eyes.
485 —GNOMES! o'er the waste YOU led your myriad powers,
Climb'd on the whirls, and aim'd the flinty showers!—
Onward resistless rolls the infuriate surge,
Clouds follow clouds, and mountains mountains urge;
Wave over wave the driving desert swims,
490 Bursts o'er their heads, inhumes their struggling limbs;
Man mounts on man, on camels camels rush,
Hosts march o'er hosts, and nations nations crush,—
Wheeling in air the winged islands fall,
And one great earthy Ocean covers all!—
495 Then ceased the storm,—NIGHT bow'd his Ethiop brow
To earth, and listen'd to the groans below,—
Grim HORROR shook,—awhile the living hill
Heaved with convulsive throes,—and all was still!
[And stalking turrets. l. 478. “At one o'clock we alighted
among some
acacia trees at Waadi el Halboub, having gone twenty-one miles. We
were
here at once surprised and terrified by a sight surely one of the
most
magnificent in the world. In that vast expanse of desert, from W.
to
N.W. of us, we saw a number of prodigious pillars of sand at
different
distances, at times moving with great celerity, at others stalking
on
with a majestic slowness; at intervals we thought they were coming
in a
very few minutes to overwhelm us; and small quantities of sand did
actually more than once reach us. Again they would retreat so as to
be
almost out of sight, their tops reaching to the very clouds. There
the
tops often separated from the bodies; and these, once disjoined,
dispersed in the air, and did not appear more. Sometimes they were
broken in the middle, as if struck with large cannon-shot. About
noon
they began to advance with considerable swiftness upon us, the wind
being very strong at north. Eleven of them ranged along side of us
about
the distance of three miles. The greatest diameter of the largest
appeared to me at that distance as if it would measure ten feet.
They
retired from us with a wind at S.E. leaving an impression upon my
mind
to which I can give no name, though surely one ingredient in it was
fear, with a considerable deal of wonder and astonishment. It was
in
vain to think of flying; the swiftest horse, or fastest sailing
ship,
could be of no use to carry us out of this danger; and the full
persuasion of this rivetted me as if to the spot where I stood.
“The same appearance of moving pillars of sand presented themselves
to
us this day in form and disposition like those we had seen at Waadi
Halboub, only they seemed to be more in number and less in size.
They
came several times in a direction close upon us, that is, I
believe,
within less than two miles. They began immediately after sun rise
like a
thick wood and almost darkened the sun. His rays shining through
them
for near an hour, gave them an appearance of pillars of fire. Our
people
now became desperate, the Greeks shrieked out and said it was the
day of
judgment; Ismael pronounced it to be hell; and the Turcorories,
that the
world was on fire.” Bruce's Travels, Vol. IV. p. 553,-555.
From this account it would appear, that the eddies of wind were
owing to
the long range of broken rocks, which bounded one side of the sandy
desert, and bent the currents of air, which struck against their
sides;
and were thus like the eddies in a stream of water, which falls
against
oblique obstacles. This explanation is probably the true one, as
these
whirl-winds were not attended with rain or lightening like the
tornadoes
of the West-Indies.]
IX. “GNOMES! whose fine forms, impassive as the air,
500 Shrink with soft sympathy for human care;
Who glide unseen, on printless slippers borne,
Beneath the waving grass, and nodding corn;
Or lay your tiny limbs, when noon-tide warms,
Where shadowy cowslips stretch their golden arms,—
505 So mark'd on orreries in lucid signs,
Star'd with bright points the mimic zodiac shines;
Borne on fine wires amid the pictured skies
With ivory orbs the planets set and rise;
Round the dwarf earth the pearly moon is roll'd,
510 And the sun twinkling whirls his rays of gold.—
Call your bright myriads, march your mailed hosts,
With spears and helmets glittering round the coasts;
Thick as the hairs, which rear the Lion's mane,
Or fringe the Boar, that bays the hunter-train;
515 Watch, where proud Surges break their treacherous mounds,
And sweep resistless o'er the cultured grounds;
Such as erewhile, impell'd o'er Belgia's plain,
Roll'd her rich ruins to the insatiate main;
With piles and piers the ruffian waves engage,
520 And bid indignant Ocean stay his rage.
[So mark'd on orreries. l. 505. The first orrery was
constructed by a
Mr. Rowley, a mathematician born at Lichfield; and so named from
his
patron the Earl of Orrery. Johnson's Dictionary.]
“Where, girt with clouds, the rifted mountain yawns,
And chills with length of shade the gelid lawns,
Climb the rude steeps, the granite-cliffs surround,
Pierce with steel points, with wooden wedges wound;
525 Break into clays the soft volcanic slaggs,
Or melt with acid airs the marble craggs;
Crown the green summits with adventurous flocks,
And charm with novel flowers the wondering rocks.
—So when proud Rome the Afric Warrior braved,
530 And high on Alps his crimson banner waved;
While rocks on rocks their beetling brows oppose
With piny forests, and unfathomed snows;
Onward he march'd, to Latium's velvet ground
With fires and acids burst the obdurate bound,
535 Wide o'er her weeping vales destruction hurl'd,
And shook the rising empire of the world.
[The granite-cliffs. l. 523. On long exposure to air the
granites or
porphories of this country exhibit a ferrugenous crust, the iron
being
calcined by the air first becomes visible, and is then washed away
from
the external surface, which becomes white or grey, and thus in time
seems to decompose. The marbles seem to decompose by loosing their
carbonic acid, as the outside, which has been long exposed to the
air,
does not seem to effervesce so hastily with acids as the parts more
recently broken. The immense quantity of carbonic acid, which
exists in
the many provinces of lime-stone, if it was extricated and
decomposed
would afford charcoal enough for fuel for ages, or for the
production of
new vegetable or animal bodies. The volcanic slaggs on Mount
Vesuvius
are said by M. Ferber to be changed into clay by means of the
sulphur-
acid, and even pots made of clay and burnt or vitrified are said by
him
to be again reducible to ductile clay by the volcanic steams.
Ferber's
Travels through Italy, p. 166.]
[Wooden wedges wound. l. 524. It is usual in seperating
large mill-
stones from the siliceous sand-rocks in some parts of Derbyshire to
bore
horizontal holes under them in a circle, and fill these with pegs
made
of dry wood, which gradually swell by the moisture of the earth,
and in
a day or two lift up the mill-stone without breaking it.]
[With fires and acids. l. 534. Hannibal was said to erode
his way over
the Alps by fire and vinegar. The latter is supposed to allude to
the
vinegar and water which was the beverage of his army. In respect to
the
former it is not improbable, but where wood was to be had in great
abundance, that fires made round limestone precipices would calcine
them
to a considerable depth, the night-dews or mountain-mists would
penetrate these calcined parts and pulverize them by the force of
the
steam which the generated heat would produce, the winds would
disperse
this lime-powder, and thus by repeated fires a precipice of
lime-stone
might be destroyed and a passage opened. It should be added, that
according to Ferber's observations, these Alps consist of
lime-stone.
Letters from Italy.]
X. “Go, gentle GNOMES! resume your vernal toil,
Seek my chill tribes, which sleep beneath the soil;
On grey-moss banks, green meads, or furrow'd lands
540 Spread the dark mould, white lime, and crumbling sands;
Each bursting bud with healthier juices feed,
Emerging scion, or awaken'd seed.
So, in descending streams, the silver Chyle
Streaks with white clouds the golden floods of bile;
545 Through each nice valve the mingling currents glide,
Join their fine rills, and swell the sanguine tide;
Each countless cell, and viewless fibre seek,
Nerve the strong arm, and tinge the blushing cheek.
“Oh, watch, where bosom'd in the teeming earth,
550 Green swells the germ, impatient for its birth;
Guard from rapacious worms its tender shoots,
And drive the mining beetle from its roots;
With ceaseless efforts rend the obdurate clay,
And give my vegetable babes to day!
555 —Thus when an Angel-form, in light array'd,
Like HOWARD pierced the prison's noisome shade;
Where chain'd to earth, with eyes to heaven upturn'd,
The kneeling Saint in holy anguish mourn'd;—
Ray'd from his lucid vest, and halo'd brow
560 O'er the dark roof celestial lustres glow,
“PETER, arise!” with cheering voice He calls,
And sounds seraphic echo round the walls;
Locks, bolts, and chains his potent touch obey,
And pleased he leads the dazzled Sage to day.
565 XI. “YOU! whose fine fingers fill the organic cells,
With virgin earth, of woods and bones and shells;
Mould with retractile glue their spongy beds,
And stretch and strengthen all their fibre-threads.—
Late when the mass obeys its changeful doom,
570 And sinks to earth, its cradle and its tomb,
GNOMES! with nice eye the slow solution watch,
With fostering hand the parting atoms catch,
Join in new forms, combine with life and sense,
And guide and guard the transmigrating Ens.
[Mould with retractile glue. l. 567. The constituent parts
of animal
fibres are believed to be earth and gluten. These do not seperate
except
by long putrefaction or by fire. The earth then effervesces with
acids,
and can only be converted into glass by the greatest force of fire.
The
gluten has continued united with the earth of the bones above 2000
years
in Egyptian mummies; but by long exposure to air or moisture it
diffolves and leaves only the earth. Hence bones long buried, when
exposed to the air, absorb moisture and crumble into powder. Phil.
Trans. No. 475. The retractibility or elasticity of the animal
fibre
depends on the gluten; and of these fibres are composed the
membranes
muscles and bones. Haller. Physiol. Tom. I, p. 2.
For the chemical decomposition of animal and vegetable bodies see
the
ingenious work of Lavoisier, Traite de Chimie, Tom. I. p. 132. who
resolves all their component parts into oxygene, hydrogene,
carbone, and
azote, the three former of which belong principally to vegetable
and the
last to animal matter.]
[The transmigrating Ens. l. 574, The perpetual circulation
of matter
in the growth and dissolution of vegetable and animal bodies seems
to
have given Pythagoras his idea of the metempsycosis or
transmigration of
spirit; which was afterwards dressed out or ridiculed in variety of
amusing fables. Other philosophers have supposed, that there are
two
different materials or essences, which fill the universe. One of
these,
which has the power of commencing or producing motion, is called
spirit;
the other, which has the power of receiving and of communicating
motion,
but not of beginning it, is called matter. The former of these is
supposed to be diffused through all space, filling up the
interstices of
the suns and planets, and constituting the gravitations of the
sidereal
bodies, the attractions of chemistry, with the spirit of
vegetation, and
of animation. The latter occupies comparatively but small space,
constituting the solid parts of the suns and planets, and their
atmospheres. Hence these philosophers have supposed, that both
matter
and spirit are equally immortal and unperishable; and that on the
dissolution of vegetable or animal organization, the matter returns
to
the general mass of matter; and the spirit to the general mass of
spirit, to enter again into new combinations, according to the
original
idea of Pythagoras.
The small apparent quantity of matter that exists in the universe
compared to that of spirit, and the short time in which the
recrements
of animal or vegetable bodies become again vivified in the forms of
vegetable mucor or microscopic insects, seems to have given rise to
another curious fable of antiquity. That Jupiter threw down a large
handful of souls upon the earth, and left them to scramble for the
few
bodies which were to be had.]
575 “So when on Lebanon's sequester'd hight
The fair ADONIS left the realms of light,
Bow'd his bright locks, and, fated from his birth
To change eternal, mingled with the earth;—
With darker horror shook the conscious wood,
580 Groan'd the sad gales, and rivers blush'd with blood;
On cypress-boughs the Loves their quivers hung,
Their arrows scatter'd, and their bows unstrung;
And BEAUTY'S GODDESS, bending o'er his bier,
Breathed the soft sigh, and pour'd the tender tear.—
585 Admiring PROSERPINE through dusky glades
Led the fair phantom to Elysian shades,
Clad with new form, with finer sense combined,
And lit with purer flame the ethereal mind.
—Erewhile, emerging from infernal night,
590 The bright Assurgent rises into light,
Leaves the drear chambers of the insatiate tomb,
And shines and charms with renovated bloom.—
While wondering Loves the bursting grave surround,
And edge with meeting wings the yawning ground,
595 Stretch their fair necks, and leaning o'er the brink
View the pale regions of the dead, and shrink;
Long with broad eyes ecstatic BEAUTY stands,
Heaves her white bosom, spreads her waxen hands;
Then with loud shriek the panting Youth alarms,
600 “My Life! my Love!” and springs into his arms.”
[Adonis. l. 576. The very antient story of the beautiful
Adonis
passing one half of the year with Venus, and the other with
Proserpine
alternately, has had variety of interpretations. Some have supposed
that
it allegorized the summer and winter solstice; but this seems too
obvious a fact to have needed an hieroglyphic emblem. Others have
believed it to represent the corn, which was supposed to sleep in
the
earth during the winter months, and to rise out of it in summer.
This
does not accord with the climate of Egypt, where the harvest soon
follows the seed-time.
It seems more probably to have been a story explaining some
hieroglyphic
figures representing the decomposition and resuscitation of animal
matter; a sublime and interesting subject, and which seems to have
given
origin to the doctrine of the transmigration, which had probably
its
birth also from the hieroglyphic treasures of Egypt. It is
remarkable
that the cypress groves in the ancient greek writers, as in
Theocritus,
were dedicated to Venus; and afterwards became funereal emblems.
Which
was probably occasioned by the Cypress being an accompaniment of
Venus
in the annual processions, in which she was supposed to lament over
the
funeral of Adonis; a ceremony which obtained over all the eastern
world
from great antiquity, and is supposed to be referred to by Ezekiel,
who
accuses the idolatrous woman of weeping for Thammus.]
The GODDESS ceased,—the delegated throng
O'er the wide plains delighted rush along;
In dusky squadrons, and in shining groups,
Hosts follow hosts, and troops succeed to troops;
605 Scarce bears the bending grass the moving freight,
And nodding florets bow beneath their weight.
So when light clouds on airy pinions sail,
Flit the soft shadows o'er the waving vale;
Shade follows shade, as laughing Zephyrs drive,
610 And all the chequer'd landscape seems alive.
[Zephyrs drive. l. 609. These lines were originally written
thus,
Shade follows shade by laughing Zephyrs drove,
And all the chequer'd landscape seems to move.
but were altered on account of the supposed false grammar in using
the
word drove for driven, according to the opinion of Dr. Lowth: at
the
same time it may be observed, 1. that this is in many cases only an
ellipsis of the letter n at the end of the word; as froze,
for frozen;
wove, for woven; spoke, for spoken; and that then the participle
accidentally becomes similar to the past tense: 2. that the
language
seems gradually tending to omit the letter n in other kind
of words
for the sake of euphony; as housen is become houses; eyne, eyes;
thine,
thy, &c. and in common conversation, the words forgot, spoke,
froze,
rode, are frequently used for forgotten, spoken, frozen, ridden. 3.
It
does not appear that any confusion would follow the indiscriminate
use
of the same word for the past tense and the participle passive,
since
the auxiliary verb have, or the preceding noun or pronoun
always
clearly distinguishes them: and lastly, rhime-poetry must lose the
use
of many elegant words without this license.]
Argument of the Third Canto.
Address to the Nymphs. I. Steam rises from the ocean, floats in
clouds,
descends in rain and dew, or is condensed on hills, produces
springs,
and rivers, and returns to the sea. So the blood circulates through
the
body and returns to the heart. 11. II. 1. Tides, 57. 2. Echinus,
nautilus, pinna, cancer. Grotto of a mermaid. 65. 3. Oil stills the
waves. Coral rocks. Ship-worm, or Teredo. Maelstrome, a whirlpool
on the
coast of Norway. 85. III. Rivers from beneath the snows on the
Alps. The
Tiber. 103. IV. Overflowing of the Nile from African Monsoons, 129.
V.
1. Giesar, a boiling fountain in Iceland, destroyed by inundation,
and
consequent earthquake, 145. 2. Warm medicinal springs. Buxton. Duke
and
Dutchess of Devonshire. 157. VI. Combination of vital air and
inflammable gas produces water. Which is another source of springs
and
rivers. Allegorical loves of Jupiter and Juno productive of vernal
showers. 201. VII. Aquatic Taste. Distant murmur of the sea by
night.
Sea-horse. Nereid singing. 261. VIII. The Nymphs of the river
Derwent
lament the death of Mrs. French, 297. IX. Inland navigation.
Monument
for Mr. Brindley, 341. X. Pumps explained. Child sucking. Mothers
exhorted to nurse their children. Cherub sleeping. 365. XI. Engines
for
extinguishing fire. Story of two lovers perishing in the flames.
397.
XII. Charities of Miss Jones, 447. XIII. Marshes drained. Hercules
conquers Achilous. The horn of Plenty. 483. XIV. Showers. Dews.
Floating
lands with water. Lacteal system in animals. Caravan drinking. 529.
Departure of the Nymphs like water spiders; like northern nations
skaiting on the ice. 569.
THE
ECONOMY OF VEGETATION.
AGAIN the GODDESS speaks!—glad Echo swells
The tuneful tones along her shadowy dells,
Her wrinkling founts with soft vibration shakes,
Curls her deep wells, and rimples all her lakes,
5 Thrills each wide stream, Britannia's isle that laves,
Her headlong cataracts, and circumfluent waves.
—Thick as the dews, which deck the morning flowers,
Or rain-drops twinkling in the sun-bright showers,
Fair Nymphs, emerging in pellucid bands,
10 Rise, as she turns, and whiten all the lands.
I. “YOUR buoyant troops on dimpling ocean tread,
Wafting the moist air from his oozy bed,
AQUATIC NYMPHS!—YOU lead with viewless march
The winged vapours up the aerial arch,
15 On each broad cloud a thousand sails expand,
And steer the shadowy treasure o'er the land,
Through vernal skies the gathering drops diffuse,
Plunge in soft rains, or sink in silver dews.—
YOUR lucid bands condense with fingers chill
20 The blue mist hovering round the gelid hill;
In clay-form'd beds the trickling streams collect,
Strain through white sands, through pebbly veins direct;
Or point in rifted rocks their dubious way,
And in each bubbling fountain rise to day.
[The winged vapours. l. 14. See additional note No. XXV. on
evaporation.]
[On each broad cloud. l. 15. The clouds consist of condensed
vapour,
the particles of which are too small separately to overcome the
tenacity
of the air, and which therefore do not descend. They are in such
small
spheres as to repel each other, that is, they are applied to each
other
by such very small surfaces, that the attraction of the particles
of
each drop to its own centre is greater than its attraction to the
surface of the drop in its vicinity; every one has observed with
what
difficulty small spherules of quicksilver can be made to unite,
owing to
the same cause; and it is common to see on riding through shallow
water
on a clear day, numbers of very small spheres of water as they are
thrown from the horses feet run along the surface for many yards
before
they again unite with it. In many cases these spherules of water,
which
compose clouds, are kept from uniting by a surplus of electric
fluid;
and fall in violent showers as soon as that is withdrawn from them,
as
in thunder storms. See note on Canto I. l. 553.
If in this state a cloud becomes frozen, it is torn to pieces in
its
descent by the friction of the air, and falls in white flakes of
snow.
Or these flakes are rounded by being rubbed together by the winds,
and
by having their angles thawed off by the warmer air beneath as they
descend; and part of the water produced by these angles thus
dissolved
is absorbed into the body of the hailstone, as may be seen by
holding a
lump of snow over a candle, and there becomes frozen into ice by
the
quantity of cold which the hailstone possesses beneath the freezing
point, or which is produced by its quick evaporation in falling;
and
thus hailstones are often found of greater or less density
according as
they consist of a greater portion of snow or ice. If hailstones
consisted of the large drops of showers frozen in their descent,
they
would consist of pure transparent ice.
As hail is only produced in summer, and is always attended with
storms,
some philosophers have believed that the sudden departure of
electricity
from a cloud may effect something yet unknown in this phenomenon;
but it
may happen in summer independent of electricity, because the
aqueous
vapour is then raised higher in the atmosphere, whence it has
further to
fall, and there is warmer air below for it to fall through.]
[Or sink in silver dews. l. 18. During the coldness of the
night the
moisture before dissolved in the air is gradually precipitated, and
as
it subsides adheres to the bodies it falls upon. Where the
attraction of
the body to the particles of water is greater than the attractions
of
those particles to each other, it becomes spread upon their
surface, or
slides down them in actual contact; as on the broad parts of the
blades
of moist grass: where the attraction of the surface to the water is
less
than the attraction of the particles of water to each other, the
dew
stands in drops; as on the points and edges of grass or gorse,
where the
surface presented to the drop being small it attracts it so little
as
but just to support it without much changing its globular form:
where
there is no attraction between the vegetable surface and the dew
drops,
as on cabbage leaves, the drop does not come into contact with the
leaf,
but hangs over it repelled, and retains it natural form, composed
of the
attraction and pressure of its own parts, and thence looks like
quicksilver, reflecting light from both its surfaces. Nor is this
owing
to any oiliness of the leaf, but simply to the polish of its
surface, as
a light needle may be laid on water in the same manner without
touching
it; for as the attractive powers of polished surfaces are greater
when
in actual contact, so the repulsive power is greater before
contact.]
[The blue mist. l. 20. Mists are clouds resting on the
ground, they
generally come on at the beginning of night, and either fill the
moist
vallies, or hang on the summits of hills, according to the degree
of
moisture previously dissolved, and the eduction of heat from them.
The
air over rivers during the warmth of the day suspends much
moisture, and
as the changeful surface of rivers occasions them to cool sooner
than
the land at the approach of evening, mists are most frequently seen
to
begin over rivers, and to spread themselves over moist grounds, and
fill
the vallies, while the mists on the tops of mountains are more
properly
clouds, condensed by the coldness of their situation.
On ascending up the side of a hill from a misty valley, I have
observed
a beautiful coloured halo round the moon when a certain thickness
of
mist was over me, which ceased to be visible as soon as I emerged
out of
it; and well remember admiring with other spectators the shadow of
the
three spires of the cathedral church at Lichfield, the moon rising
behind it, apparently broken off, and lying distinctly over our
heads as
if horizontally on the surface of the mist, which arose about as
high as
the roof of the church. There are some curious remarks on shadows
or
reflexions seen on the surface of mists from high mountains in
Ulloa's
Voyages. The dry mist of summer 1783, was probably occasioned by
volcanic eruption, as mentioned in note on Chunda, Vol. II. and
therefore more like the atmosphere of smoke which hangs on still
days
over great cities.
There is a dry mist, or rather a diminished transparence of the
air,
which according to Mr. Saussure accompanies fair weather, while
great
transparence of air indicates rain. Thus when large rivers two
miles
broad, such as at Liverpool, appear narrow, it is said to
prognosticate
rain; and when wide, fair weather. This want of transparence of the
air
in dry weather, may be owing to new combinations or decompositions
of
the vapours dissolved in it, but wants further investigation.
Essais sur
L'Hygromet, p. 357.]
[Round the gelid hill. l. 20. See additional notes, No.
XXVI. on the
origin of springs.]
25 “NYMPHS! YOU then guide, attendant from their source,
The associate rills along their sinuous course;
Float in bright squadrons by the willowy brink,
Or circling slow in limpid eddies sink;
Call from her crystal cave the Naiad-Nymph,
30 Who hides her fine form in the passing lymph,
And, as below she braids her hyaline hair,
Eyes her soft smiles reflected in the air;
Or sport in groups with River-Boys, that lave
Their silken limbs amid the dashing wave;
35 Pluck the pale primrose bending from its edge,
Or tittering dance amid the whispering sedge.—
“Onward YOU pass, the pine-capt hills divide,
Or feed the golden harvests on their side;
The wide-ribb'd arch with hurrying torrents fill,
40 Shove the slow barge, or whirl the foaming mill.
OR lead with beckoning hand the sparkling train
Of refluent water to its parent main,
And pleased revisit in their sea-moss vales
Blue Nereid-forms array'd in shining scales,
45 Shapes, whose broad oar the torpid wave impels,
And Tritons bellowing through their twisted shells.
“So from the heart the sanguine stream distils,
O'er Beauty's radiant shrine in vermil rills,
Feeds each fine nerve, each slender hair pervades,
50 The skins bright snow with living purple shades,
Each dimpling cheek with warmer blushes dyes,
Laughs on the lips, and lightens in the eyes.
—Erewhile absorb'd, the vagrant globules swim
From each fair feature, and proportion'd limb,
55 Join'd in one trunk with deeper tint return
To the warm concave of the vital urn.
II. 1.”AQUATIC MAIDS! YOU sway the mighty realms
Of scale and shell, which Ocean overwhelms;
As Night's pale Queen her rising orb reveals,
60 And climbs the zenith with refulgent wheels,
Car'd on the foam your glimmering legion rides,
Your little tridents heave the dashing tides,
Urge on the sounding shores their crystal course,
Restrain their fury, or direct their force.
[Car'd on the foam. l. 61. The phenomena of the tides have
been well
investigated and satisfactorily explained by Sir Isaac Newton and
Dr.
Halley from the reciprocal gravitations of the earth, moon, and
sun. As
the earth and moon move round a centre of motion near the earth's
surface, at the same time that they are proceeding in their annual
orbit
round the sun, it follows that the water on the side of the earth
nearest this centre of motion between the earth and moon will be
more
attracted by the moon, and the waters on the opposite side of the
earth
will be less attracted by the moon, than the central parts of the
earth.
Add to this that the centrifugal force of the water on the side of
the
earth furthest from the centre of the motion, round which the earth
and
moon move, (which, as was said before, is near the surface of the
earth)
is greater than that on the opposite side of the earth. From both
these
causes it is easy to comprehend that the water will rise on two
sides of
the earth, viz. on that nearest to the moon, and its opposite side,
and
that it will be flattened in consequence at the quadratures, and
thus
produce two tides in every lunar day, which consists of about
twenty-
four hours and forty-eight minutes.
These tides will be also affected by the solar attraction when it
coincides with the lunar one, or opposes it, as at new and full
moon,
and will also be much influenced by the opposing shores in every
part of
the earth.
Now as the moon in moving round the centre of gravity between
itself and
the earth describes a much larger orbit than the earth describes
round
the same centre, it follows that the centrifugal motion on the side
of
the moon opposite to the earth must be much greater than the
centrifugal
motion of the side of the earth opposite to the moon round the same
centre. And secondly, as the attraction of the earth exerted on the
moon's surface next to the earth is much greater than the
attraction of
the moon exerted on the earth's surface, the tides on the lunar
sea, (if
such there be,) should be much greater than those of our ocean. Add
to
this that as the same face of the moon always is turned to the
earth,
the lunar tides must be permanent, and if the solid parts of the
moon be
spherical, must always cover the phasis next to us. But as there
are
evidently hills and vales and volcanos on this side of the moon,
the
consequence is that the moon has no ocean, or that it is frozen.]
65 2.”NYMPHS! YOU adorn, in glossy volumes roll'd,
The gaudy conch with azure, green, and gold.
You round Echinus ray his arrowy mail,
Give the keel'd Nautilus his oar and sail;
Firm to his rock with silver cords suspend
70 The anchor'd Pinna, and his Cancer-friend;
With worm-like beard his toothless lips array,
And teach the unwieldy Sturgeon to betray.—
Ambush'd in weeds, or sepulcher'd in sands,
In dread repose He waits the scaly bands,
75 Waves in red spires the living lures, and draws
The unwary plunderers to his circling jaws,
Eyes with grim joy the twinkling shoals beset,
And clasps the quick inextricable net.
You chase the warrior Shark, and cumberous Whale,
80 And guard the Mermaid in her briny vale;
Feed the live petals of her insect-flowers,
Her shell-wrack gardens, and her sea-fan bowers;
With ores and gems adorn her coral cell,
And drop a pearl in every gaping shell.
[The gaudy conch. l. 66. The spiral form of many shells seem
to have
afforded a more frugal manner of covering the long tail of the fish
with
calcareous armour; since a single thin partition between the
adjoining
circles of the fish was sufficient to defend both surfaces, and
thus
much cretaceous matter is saved; and it is probable that from this
spiral form they are better enabled to feel the vibrations of the
element in which they exist. See note on Canto IV. l. 162. This
cretaceous matter is formed by a mucous secretion from the skin of
the
fish, as is seen in crab-fish, and others which annually cast their
shells, and is at first a soft mucous covering, (like that of a
hen's
egg, when it is laid a day or two too soon,) and which gradually
hardens. This may also be seen in common shell snails, if a part of
their shell be broken it becomes repaired in a similar manner with
mucus, which by degrees hardens into shell.
It is probable the calculi or stones found in other animals may
have a
similar origin, as they are formed on mucous membranes, as those of
the
kidney and bladder, chalk-stones in the gout, and gall-stones; and
are
probably owing to the inflammation of the membrane where they are
produced, and vary according to the degree of inflammation of the
membrane which forms them, and the kind of mucous which it
naturally
produces. Thus the shelly matter of different shell-fish differs,
from
the courser kinds which form the shells of crabs, to the finer
kinds
which produces the mother-pearl.
The beautiful colours of some shells originate from the thinness of
the
laminae of which they consist, rather than to any colouring matter,
as
is seen in mother-pearl, which reflects different colours according
to
the obliquity of the light which falls on it. The beautiful
prismatic
colours seen on the Labrodore stone are owing to a similar cause,
viz.
the thinness of the laminae of which it consists, and has probably
been
formed from mother-pearl shells.
It is curious that some of the most common fossil shells are not
now
known in their recent state, as the cornua ammonis; and on the
contrary,
many shells which are very plentiful in their recent state, as
limpets,
sea-ears, volutes, cowries, are very rarely found fossil. Da
Costa's
Conchology, p. 163. Were all the ammoniae destroyed when the
continents
were raised? Or do some genera of animals perish by the increasing
power
of their enemies? Or do they still reside at inaccessible depths in
the
sea? Or do some animals change their forms gradually and become new
genera?]
[Echinus. Nautilus. l. 67, 68. See additional notes, No.
XXVII.]
[Pinna. Cancer. l. 70. See additional notes, No. XXVII.]
[With worm-like beard. l. 71. See additional notes, No.
XXVIII.]
[Feed the live petals. l. 82. There is a sea-insect
described by Mr.
Huges whose claws or tentacles being disposed in regular circles
and
tinged with variety of bright lively colours represent the petals
of
some most elegantly fringed and radiated flowers as the carnation,
marigold, and anemone. Philos. Trans. Abridg. Vol. IX. p. 110. The
Abbe
Dicquemarre has further elucidated the history of the actinia; and
observed their manner of taking their prey by inclosing it in these
beautiful rays like a net. Phil. Trans. Vol. LXIII. and LXV. and
LXVII.]
[And drop a pearl. l. 84. Many are the opinions both of
antient and
modern concerning the production of pearls. Mr. Reaumur thinks they
are
formed like the hard concretions in many land animals as stones of
the
bladder, gallstones, and bezoar, and hence concludes them to be a
disease of the fish, but there seems to be a stricter analogy
between
these and the calcareous productions found in crab-fish called
crab's
eyes, which are formed near the stomach of the animal, and
constitute a
reservoir of calcareous matter against the renovation of the shell,
at
which time they are re-dissolved and deposited for that purpose. As
the
internal part of the shell of the pearl oyster or muscle consists
of
mother-pearl which is a similar material to the pearl and as the
animal
has annually occasion to enlarge his shell there is reason to
suspect the
loose pearls are similar reservoirs of the pearly matter for that
purpose.]
85 3. “YOUR myriad trains o'er stagnant ocean's tow,
Harness'd with gossamer, the loitering prow;
Or with fine films, suspended o'er the deep,
Of oil effusive lull the waves to sleep.
You stay the flying bark, conceal'd beneath,
90 Where living rocks of worm-built coral breathe;
Meet fell TEREDO, as he mines the keel
With beaked head, and break his lips of steel;
Turn the broad helm, the fluttering canvas urge
From MAELSTROME'S fierce innavigable surge.
95 —'Mid the lorn isles of Norway's stormy main,
As sweeps o'er many a league his eddying train,
Vast watery walls in rapid circles spin,
And deep-ingulph'd the Demon dwells within;
Springs o'er the fear-froze crew with Harpy-claws,
100 Down his deep den the whirling vessel draws;
Churns with his bloody mouth the dread repast,
The booming waters murmuring o'er the mast.
[Or with fine films. l. 87. See additional notes, No. XXIX.]
[Where living rocks. l. 90. The immense and dangerous rocks
built by
the swarms of coral infects which rise almost perpendicularly in
the
southern ocean like walls are described in Cook's voyages, a point
of
one of these rocks broke off and stuck in the hole which it had
made in
the bottom of one of his ships, which would otherwise have perished
by
the admission of water. The numerous lime-stone rocks which consist
of a
congeries of the cells of these animals and which constitute a
great
part of the solid earth shew their prodigious multiplication in all
ages
of the world. Specimens of these rocks are to be seen in the
Lime-works
at Linsel near Newport in Shropshire, in Coal-brook Dale, and in
many
parts of the Peak of Derbyshire. The insect has been well described
by
M. Peyssonnel, Ellis, and others. Phil. Trans. Vol. XLVII. L. LII.
and
LVII.]
[Meet fell Teredo. l. 91. See additional notes, No. XXX.]
[Turn the broad helm. l 93. See additional notes, No. XXXI.]
III. “Where with chill frown enormous ALPS alarms
A thousand realms, horizon'd in his arms;
105 While cloudless suns meridian glories shed
From skies of silver round his hoary head,
Tall rocks of ice refract the coloured rays,
And Frost sits throned amid the lambent blaze;
NYMPHS! YOUR thin forms pervade his glittering piles,
110 His roofs of chrystal, and his glasy ailes;
Where in cold caves imprisoned Naiads sleep,
Or chain'd on mossy couches wake and weep;
Where round dark crags indignant waters bend
Through rifted ice, in ivory veins descend,
115 Seek through unfathom'd snows their devious track,
Heave the vast spars, the ribbed granites crack,
Rush into day, in foamy torrents shine,
And swell the imperial Danube or the Rhine.—
Or feed the murmuring TIBER, as he laves
120 His realms inglorious with diminish'd waves,
Hears his lorn Forum sound with Eunuch-strains,
Sees dancing slaves insult his martial plains;
Parts with chill stream the dim religious bower,
Time-mouldered bastion, and dismantled tower;
125 By alter'd fanes and nameless villas glides,
And classic domes, that tremble on his sides;
Sighs o'er each broken urn, and yawning tomb,
And mourns the fall of LIBERTY and ROME.
[Where round dark craggs. l. 113. See additional notes, No.
XXXII.]
[Heave the vast spars. l. 116. Water in descending down
elevated
situations if the outlet for it below is not sufficient for its
emission
acts with a force equal to the height of the column, as is seen in
an
experimental machine called the philosophical bellows, in which a
few
pints of water are made to raise many hundred pounds. To this cause
is
to be ascribed many large promontories of ice being occasionally
thrown
down from the glaciers; rocks have likewise been thrown from the
sides
of mountains by the same cause, and large portions of earth have
been
removed many hundred yards from their situations at the foot of
mountains. On inspecting the locomotion of about thirty acres of
earth
with a small house near Bilder's Bridge in Shropshire, about twenty
years ago, from the foot of a mountain towards the river, I well
remember it bore all the marks of having been thus lifted up,
pushed
away, and as it were crumpled into ridges, by a column of water
contained in the mountain.
From water being thus confined in high columns between the strata
of
mountainous countries it has often happened that when wells or
perforations have been made into the earth, that springs have
arisen
much above the surface of the new well. When the new bridge was
building
at Dublin Mr. G. Semple found a spring in the bed of the river
where he
meant to lay the foundation of a pierre, which, by fixing iron
pipes
into it, he raised many feet. Treatise on Building in Water, by G.
Semple. From having observed a valley north-west of St. Alkmond's
well
near Derby, at the head of which that spring of water once probably
existed, and by its current formed the valley, (but which in after
times
found its way out in its present situation,) I suspect that St.
Alkmond's well might by building round it be raised high enough to
supply many streets in Derby with spring-water which are now only
supplied with river-water. See an account of an artificial spring
of
water, Phil. Trans. Vol. LXXV. p. 1.
In making a well at Sheerness the water rose 300 feet above its
source
in the well. Phil. Trans. Vol. LXXIV. And at Hartford in
Connecticut
there is a well which was dug seventy feet deep before water was
found,
then in boring an augur-hole through a rock the water rose so fast
as to
make it difficult to keep it dry by pumps till they could blow the
hole
larger by gunpowder, which was no sooner accomplished than it
filled and
run over, and has been a brook for near a century. Travels through
America. Lond. 1789. Lane.]
IV. “Sailing in air, when dark MONSOON inshrouds
130 His tropic mountains in a night of clouds;
Or drawn by whirlwinds from the Line returns,
And showers o'er Afric all his thousand urns;
High o'er his head the beams of SIRIUS glow,
And, Dog of Nile, ANUBIS barks below.
135 NYMPHS! YOU from cliff to cliff attendant guide
In headlong cataracts the impetuous tide;
Or lead o'er wastes of Abyssinian sands
The bright expanse to EGYPT'S shower-less lands.
—Her long canals the sacred waters fill,
140 And edge with silver every peopled hill;
Gigantic SPHINX in circling waves admire;
And MEMNON bending o'er his broken lyre;
O'er furrow'd glebes and green savannas sweep,
And towns and temples laugh amid the deep.
[Dark monsoon inshrouds. l. 129. When from any peculiar
situations of
land in respect to sea the tropic becomes more heated, when the sun
is
vertical over it, than the line, the periodical winds called
monsoons
are produced, and these are attended by rainy seasons; for as the
air at
the tropic is now more heated than at the line it ascends by
decrease of
its specific gravity, and floods of air rush in both from the South
West
and North East, and these being one warmer than the other the rain
is
precipitated by their mixture as observed by Dr. Hutton. See
additional
notes, No. XXV. All late travellers have ascribed the rise of the
Nile
to the monsoons which deluge Nubia and Abyssinia with rain. The
whirling
of the ascending air was even seen by Mr. Bruce in Abyssinia; he
says,
“every morning a small cloud began to whirl round, and presently
after
the whole heavens became covered with clouds,” by this vortex of
ascending air the N.E. winds and the S.W. winds, which flow in to
supply
the place of the ascending column, became mixed more rapidly and
deposited their rain in greater abundance.
Mr. Volney observes that the time of the rising of the Nile
commences
about the 19th of June, and that Abyssinia and the adjacent parts
of
Africa are deluged with rain in May, June, and July, and produce a
mass
of water which is three months in draining off. The Abbe Le Pluche
observes that as Sirius, or the dog-star, rose at the time of the
commencement of the flood its rising was watched by the
astronomers, and
notice given of the approach of inundation by hanging the figure of
Anubis, which was that of a man with a dog's head, upon all their
temples. Histoire de Ciel.]
[Illustration: Fertilization of Egypt.]
[Egypt's shower-less lands. l. 138. There seem to be two
situations
which may be conceived to be exempted from rain falling upon them,
one
where the constant trade-winds meet beneath the line, for here two
regions of warm air are mixed together, and thence do not seem to
have
any cause to precipitate their vapour; and the other is, where the
winds
are brought from colder climates and become warmer by their contact
with
the earth of a warmer one. Thus Lower Egypt is a flat country
warmed by
the sun more than the higher lands of one side of it, and than the
Mediterranean on the other; and hence the winds which blow over it
acquire greater warmth, which ever way they come, than they
possessed
before, and in consequence have a tendency to acquire and not to
part
with their vapour like the north-east winds of this country. There
is
said to be a narrow spot upon the coast of Peru where rain seldom
occurs, at the same time according to Ulloa on the mountainous
regions
of the Andes beyond there is almost perpetual rain. For the wind
blows
uniformly upon this hot part of the coast of Peru, but no cause of
devaporation occurs till it begins to ascend the mountainous Andes,
and
then its own expansion produces cold sufficient to condense its
vapour.]
145 V. 1. “High in the frozen North where HECCLA glows,
And melts in torrents his coeval snows;
O'er isles and oceans sheds a sanguine light,
Or shoots red stars amid the ebon night;
When, at his base intomb'd, with bellowing sound
150 Fell GIESAR roar'd, and struggling shook the ground;
Pour'd from red nostrils, with her scalding breath,
A boiling deluge o'er the blasted heath;
And, wide in air, in misty volumes hurl'd
Contagious atoms o'er the alarmed world;
155 NYMPHS! YOUR bold myriads broke the infernal spell,
And crush'd the Sorceress in her flinty cell.
[Fell Giesar roar'd. l. 150. The boiling column of water at
Giesar in
Iceland was nineteen feet in diameter, and sometimes rose to the
height
of ninety-two feet. On cooling it deposited a siliceous matter or
chalcedony forming a bason round its base. The heat of this water
before
it rose out of the earth could not be ascertained, as water looses
all
its heat above 212 (as soon as it is at liberty to expand) by the
exhalation of a part, but the flinty bason which is deposited from
it
shews that water with great degrees of heat will dissolve siliceous
matter. Van Troil's Letters on Iceland. Since the above account in
the
year 1780 this part of Iceland has been destroyed by an earthquake
or
covered with lava, which was probably effected by the force of
aqueous
steam, a greater quantity of water falling on the subterraneous
fires
than could escape by the antient outlets and generating an
increased
quantity of vapour. For the dispersion of contagious vapours from
volcanos see an account of the Harmattan in the notes on Chunda,
Vol. II.]
2. “Where with soft fires in unextinguish'd urns,
Cauldron'd in rock, innocuous Lava burns;
On the bright lake YOUR gelid hands distil
160 In pearly mowers the parsimonious rill;
And, as aloft the curling vapours rise
Through the cleft roof, ambitious for the skies,
In vaulted hills condense the tepid steams,
And pour to HEALTH the medicated streams.
165 —So in green vales amid her mountains bleak
BUXTONIA smiles, the Goddess-Nymyh of Peak;
Deep in warm waves, and pebbly baths she dwells,
And calls HYGEIA to her sainted wells.
[Buxtonia smiles. l. 166. Some arguments are mentioned in
the note on
Fucus Vol. II. to shew that the warm springs of this country do not
arise from the decomposition of pyrites near the surface of the
earth,
but that they are produced by steam rising up the fissures of the
mountains from great depths, owing to water falling on
subterraneous
fires, and that this steam is condensed between the strata of the
incumbent mountains and collected into springs. For further proofs
on
this subject the reader is referred to a Letter from Dr. Darwin in
Mr.
Pilkington's View of Derbyshire, Vol I. p. 256.]
“Hither in sportive bands bright DEVON leads
170 Graces and Loves from Chatsworth's flowery meads.—
Charm'd round the NYMPH, they climb the rifted rocks;
And steep in mountain-mist their golden locks;
On venturous step her sparry caves explore,
And light with radiant eyes her realms of ore;
175 —Oft by her bubbling founts, and shadowy domes,
In gay undress the fairy legion roams,
Their dripping palms in playful malice fill,
Or taste with ruby lip the sparkling rill;
Croud round her baths, and, bending o'er the side,
180 Unclasp'd their sandals, and their zones untied,
Dip with gay fear the shuddering foot undress'd,
And quick retract it to the fringed vest;
Or cleave with brandish'd arms the lucid stream,
And sob, their blue eyes twinkling in the steam.
185 —High o'er the chequer'd vault with transient glow
Bright lustres dart, as dash the waves below;
And Echo's sweet responsive voice prolongs
The dulcet tumult of their silver tongues.—
O'er their flush'd cheeks uncurling tresses flow,
190 And dew-drops glitter on their necks of snow;
Round each fair Nymph her dropping mantle clings,
And Loves emerging shake their showery wings.
[And sob, their blue eyes. l. 184. The bath at Buxton being
of 82
degrees of heat is called a warm bath, and is so compared with
common
spring-water which possesses but 48 degrees of heat, but is
nevertheless
a cold bath compared to the heat of the body which is 98. On going
into
this bath there is therefore always a chill perceived at the first
immersion, but after having been in it a minute the chill ceases
and a
sensation of warmth succeeds though the body continues to be
immersed in
the water. The cause of this curious phenomenon is to be looked for
in
the laws of animal sensation and not from any properties of heat.
When a
person goes from clear day-light into an obscure room for a while
it
appears gloomy, which gloom however in a little time ceases, and
the
deficiency of light becomes no longer perceived. This is not solely
owing to the enlargement of the iris of the eye, since that is
performed
in an instant, but to this law of sensation, that when a less
stimulus
is applied (within certain bounds) the sensibility increases. Thus
at
going into a bath as much colder than the body as that of Buxton,
the
diminution of heat on the skin is at first perceived, but in about
a
minute the sensibility to heat increases and the nerves of the skin
are
equally excited by the lessened stimulus. The sensation of warmth
at
emerging from a cold-bath, and the pain called the hot-ach, after
the
hands have been immersed in snow, depend on the same principle,
viz. the
increased sensibility of the skin after having been previously
exposed
to a stimulus less than usual.]
“Here oft her LORD surveys the rude domain,
Fair arts of Greece triumphant in his train;
195 LO! as he steps, the column'd pile ascends,
The blue roof closes, or the crescent bends;
New woods aspiring clothe their hills with green,
Smooth slope the lawns, the grey rock peeps between;
Relenting Nature gives her hand to Taste,
200 And Health and Beauty crown the laughing waste.
[Here oft her Lord. l. 193. Alluding to the magnificent and
beautiful
crescent, and superb stables lately erected at Buxton for the
accomodation of the company by the Duke of Devonshire; and to the
plantations with which he has decorated the surrounding mountains.]
VI. “NYMPHS! YOUR bright squadrons watch with chemic eyes
The cold-elastic vapours, as they rise;
With playful force arrest them as they pass,
And to pure AIR betroth the flaming GAS.
205 Round their translucent forms at once they fling
Their rapturous arms, with silver bosoms cling;
In fleecy clouds their fluttering wings extend,
Or from the skies in lucid showers descend;
Whence rills and rivers owe their secret birth,
210 And Ocean's hundred arms infold the earth.
[And to pure air. l. 204. Until very lately water was
esteemed a
simple element, nor are all the most celebrated chemists of Europe
yet
converts to the new opinion of its decomposition. Mr. Lavoisier and
others of the French school have most ingeniously endeavoured to
shew
that water consists of pure air, called by them oxygene, and of
inflammable air, called hydrogene, with as much of the matter of
heat,
or calorique, as is necessary to preserve them in the form of gas.
Gas
is distinguished from steam by its preserving its elasticity under
the
pressure of the atmosphere, and in the greatest degrees of cold yet
known. The history of the progress of this great discovery is
detailed
in the Memoires of the Royal Academy for 1781, and the experimental
proofs of it are delivered in Lavoisier's Elements of Chemistry.
The
results of which are that water consists of eighty-five parts by
weight
of oxygene, and fifteen parts by weight of hydrogene, with a
sufficient
quantity of Calorique. Not only numerous chemical phenomena, but
many
atmospherical and vegetable facts receive clear and beautiful
elucidation from this important analysis. In the atmosphere
inflammable
air is probably perpetually uniting with vital air and producing
moisture which descends in dews and showers, while the growth of
vegetables by the assistance of light is perpetually again
decomposing
the water they imbibe from the earth, and while they retain the
inflammable air for the formation of oils, wax, honey, resin, &c.
they
give up the vital air to replenish the atmosphere.]
“So, robed by Beauty's Queen, with softer charms
SATURNIA woo'd the Thunderer to her arms;
O'er her fair limbs a veil of light she spread,
And bound a starry diadem on her head;
215 Long braids of pearl her golden tresses grac'd,
And the charm'd CESTUS sparkled round her waist.
—Raised o'er the woof, by Beauty's hand inwrought,
Breathes the soft Sigh, and glows the enamour'd Thought;
Vows on light wings succeed, and quiver'd Wiles,
220 Assuasive Accents, and seductive Smiles.
—Slow rolls the Cyprian car in purple pride,
And, steer'd by LOVE, ascends admiring Ide;
Climbs the green slopes, the nodding woods pervades,
Burns round the rocks, or gleams amid the shades.
225 —Glad ZEPHYR leads the train, and waves above
The barbed darts, and blazing torch of Love;
Reverts his smiling face, and pausing flings
Soft showers of roses from aurelian wings.
Delighted Fawns, in wreathes of flowers array'd,
230 With tiptoe Wood-Boys beat the chequer'd glade;
Alarmed Naiads, rising into air,
Lift o'er their silver urns their leafy hair;
Each to her oak the bashful Dryads shrink,
And azure eyes are seen through every chink.
235 —LOVE culls a flaming shaft of broadest wing,
And rests the fork upon the quivering string;
Points his arch eye aloft, with fingers strong
Draws to his curled ear the silken thong;
Loud twangs the steel, the golden arrow flies,
240 Trails a long line of lustre through the skies;
“'Tis done!” he shouts, “the mighty Monarch feels!”
And with loud laughter shakes the silver wheels;
Bends o'er the car, and whirling, as it moves,
His loosen'd bowstring, drives the rising doves.
245 —Pierced on his throne the slarting Thunderer turns,
Melts with soft sighs, with kindling rapture burns;
Clasps her fair hand, and eyes in fond amaze
The bright Intruder with enamour'd gaze.
“And leaves my Goddess, like a blooming bride,
250 “The fanes of Argos for the rocks of Ide?
“Her gorgeous palaces, and amaranth bowers,
“For cliff-top'd mountains, and aerial towers?”
He said; and, leading from her ivory seat
The blushing Beauty to his lone retreat,
255 Curtain'd with night the couch imperial shrouds,
And rests the crimson cushions upon clouds.—
Earth feels the grateful influence from above,
Sighs the soft Air, and Ocean murmurs love;
Etherial Warmth expands his brooding wing,
260 And in still showers descends the genial Spring.
[And steer'd by love. l. 222. The younger love, or Cupid,
the son of
Venus, owes his existence and his attributes to much later times
than
the Eros, or divine love, mentioned in Canto I. since the former is
no
where mentioned by Homer, though so many apt opportunities of
introducing him occur in the works of that immortal bard. Bacon.]
[And in still showers. l. 260. The allegorical
interpretation of the
very antient mythology which supposes Jupiter to represent the
superior
part of the atmosphere or ether, and Juno the inferior air, and
that the
conjunction of these two produces vernal showers, as alluded to in
Virgil's Georgics, is so analogous to the present important
discovery of
the production of water from pure air, or oxygene, and inflammable
air,
or hydrogene, (which from its greater levity probably resides over
the
former,) that one should be tempted to believe that the very
antient
chemists of Egypt had discovered the composition of water, and thus
represented it in their hieroglyphic figures before the invention
of
letters.
In the passage of Virgil Jupiter is called ether, and descends in
prolific showers on the bosom of Juno, whence the spring succeeds
and
all nature rejoices.
Tum pater omnipotens foecundis imbribus Aether
Conjugis in gremium laetae descendit, et omnes
Magnus alit, magno commixtus corpore, faetus.
Virg. Georg. Lib. II. l. 325.]
VII. “NYMPHS OF AQUATIC TASTE! whose placid smile
Breathes sweet enchantment o'er BRITANNIA'S isle;
Whose sportive touch in showers resplendent flings
Her lucid cataracts, and her bubbling springs;
265 Through peopled vales the liquid silver guides,
And swells in bright expanse her freighted tides.
YOU with nice ear, in tiptoe trains, pervade
Dim walks of morn or evening's silent shade;
Join the lone Nightingale, her woods among,
270 And roll your rills symphonious to her song;
Through fount-full dells, and wave-worn valleys move,
And tune their echoing waterfalls to love;
Or catch, attentive to the distant roar,
The pausing murmurs of the dashing shore;
275 Or, as aloud she pours her liquid strain,
Pursue the NEREID on the twilight main.
—Her playful Sea-horse woos her soft commands,
Turns his quick ears, his webbed claws expands,
His watery way with waving volutes wins,
280 Or listening librates on unmoving fins.
The Nymph emerging mounts her scaly seat,
Hangs o'er his glossy sides her silver feet,
With snow-white hands her arching veil detains,
Gives to his slimy lips the slacken'd reins,
285 Lifts to the star of Eve her eye serene,
And chaunts the birth of Beauty's radiant Queen.—
O'er her fair brow her pearly comb unfurls
Her beryl locks, and parts the waving curls,
Each tangled braid with glistening teeth unbinds
290 And with the floating treasure musks the winds.—
Thrill'd by the dulcet accents, as she sings,
The rippling wave in widening circles rings;
Night's shadowy forms along the margin gleam
With pointed ears, or dance upon the stream;
295 The Moon transported stays her bright career,
And maddening Stars shoot headlong from the sphere.
[Her playful seahorse. l. 277. Described form an antique
gem.]
VIII. “NYMPHS! whose fair eyes with vivid lustres glow
For human weal, and melt at human woe;
Late as YOU floated on your silver shells,
300 Sorrowing and slow by DERWENT'S willowy dells;
Where by tall groves his foamy flood he steers
Through ponderous arches o'er impetuous wears,
By DERBY'S shadowy towers reflective sweeps,
And gothic grandeur chills his dusky deeps;
305 You pearl'd with Pity's drops his velvet sides,
Sigh'd in his gales, and murmur'd in his tides,
Waved o'er his fringed brink a deeper gloom,
And bow'd his alders o'er MILCENA'S tomb.
[O'er Milcena's tomb. l. 308. In memory of Mrs. French, a
lady who to
many other elegant accomplishments added a proficiency in botany
and
natural history.]
“Oft with sweet voice She led her infant-train,
310 Printing with graceful step his spangled plain,
Explored his twinkling swarms, that swim or fly,
And mark'd his florets with botanic eye.—
“Sweet bud of Spring! how frail thy transient bloom,
“Fine film,” she cried, “of Nature's fairest loom!
315 “Soon Beauty fades upon its damask throne!”—
—Unconscious of the worm, that mined her own!—
—Pale are those lips, where soft caresses hung,
Wan the warm cheek, and mute the tender tongue,
Cold rests that feeling heart on Derwent's shore,
320 And those love-lighted eye-balls roll no more!
—HERE her sad Consort, stealing through the gloom
Of
Hangs in mute anguish o'er the scutcheon'd hearse,
Or graves with trembling style the votive verse.
325 “Sexton! oh, lay beneath this sacred shrine,
When Time's cold hand shall close my aching eyes,
Oh, gently lay this wearied earth of mine,
Where wrap'd in night my loved MILCENA lies.
“So shall with purer joy my spirit move,
330 When the last trumpet thrills the caves of Death,
Catch the first whispers of my waking love,
And drink with holy kiss her kindling breath.
“The spotless Fair, with blush ethereal warm,
Shall hail with sweeter smile returning day,
335 Rise from her marble bed a brighter form,
And win on buoyant step her airy way.
“Shall bend approved, where beckoning hosts invite,
On clouds of silver her adoring knee,
Approach with Seraphim the throne of light,
340 —And BEAUTY plead with angel-tongue for Me!”
IX. “YOUR virgin trains on BRINDLEY'S cradle smiled,
And nursed with fairy-love the unletter'd child,
Spread round his pillow all your secret spells,
Pierced all your springs, and open'd all your wells.—
345 As now on grass, with glossy folds reveal'd,
Glides the bright serpent, now in flowers conceal'd;
Far shine the scales, that gild his sinuous back,
And lucid undulations mark his track;
So with strong arm immortal BRINDLEY leads
350 His long canals, and parts the velvet meads;
Winding in lucid lines, the watery mass
Mines the firm rock, or loads the deep morass,
With rising locks a thousand hills alarms,
Flings o'er a thousand streams its silver arms,
355 Feeds the long vale, the nodding woodland laves,
And Plenty, Arts, and Commerce freight the waves.
—NYMPHS! who erewhile round BRINDLEY'S early bier
On show-white bosoms shower'd the incessant tear,
Adorn his tomb!—oh, raise the marble bust,
360 Proclaim his honours, and protect his dust!
With urns inverted, round the sacred shrine
Their ozier wreaths let weeping Naiads twine;
While on the top MECHANIC GENIUS stands,
Counts the fleet waves, and balances the lands.
[On Brindley's cradle smiled. l. 341. The life of Mr.
Brindley, whose
great abilities in the construction of canal navigation were called
forth by the patronage of the Duke of Bridgwater, may be read in
Dr.
Kippis's Biographia Britannica, the excellence of his genius is
visible
in every part of this island. He died at Turnhurst in Staffordshire
in
1772, and ought to have a monument in the cathedral church at
Lichfield.]
365 X. “NYMPHS! YOU first taught to pierce the secret caves
Of humid earth, and lift her ponderous waves;
Bade with quick stroke the sliding piston bear
The viewless columns of incumbent air;—
Press'd by the incumbent air the floods below,
370 Through opening valves in foaming torrents flow,
Foot after foot with lessen'd impulse move,
And rising seek the vacancy above.—
So when the Mother, bending o'er his charms,
Clasps her fair nurseling in delighted arms;
375 Throws the thin kerchief from her neck of snow,
And half unveils the pearly orbs below;
With sparkling eye the blameless Plunderer owns
Her soft embraces, and endearing tones,
Seeks the salubrious fount with opening lips,
380 Spreads his inquiring hands, and smiles, and sips.
[Lift her ponderous waves. l. 366. The invention of the pump
is of
very antient date, being ascribed to one Ctesebes an Athenian,
whence it
was called by the Latins machina Ctesebiana; but it was long before
it
was known that the ascent of the piston lifted the superincumbent
column
of the atmosphere, and that then the pressure of the surrounding
air on
the surface of the well below forced the water up into the vacuum,
and
that on that account in the common lifting pump the water would
rise
only about thirty-five feet, as the weight of such a column of
water was
in general an equipoise to the surrounding atmosphere. The foamy
appearance of water, when the pressure of the air over it is
diminished,
is owing to the expansion and escape of the air previously
dissolved by
it, or existing in its pores. When a child first sucks it only
presses
or champs the teat, as observed by the great Harvey, but afterwards
it
learns to make an incipient vacuum in its mouth, and acts by
removing
the pressure of the atmosphere from the nipple, like a pump.]
“CONNUBIAL FAIR! whom no fond transport warms
To lull your infant in maternal arms;
Who, bless'd in vain with tumid bosoms, hear
His tender wailings with unfeeling ear;
385 The soothing kiss and milky rill deny
To the sweet pouting lip, and glistening eye!—
Ah! what avails the cradle's damask roof,
The eider bolster, and embroider'd woof!—
Oft hears the gilded couch unpity'd plains,
390 And many a tear the tassel'd cushion stains!
No voice so sweet attunes his cares to rest,
So soft no pillow, as his Mother's breast!—
—Thus charm'd to sweet repose, when twilight hours
Shed their soft influence on celestial bowers,
395 The Cherub, Innocence, with smile divine
Shuts his white wings, and sleeps on Beauty's shrine.
[Ah! what avails. l. 387. From an elegant little poem of Mr.
Jerningham's intitled Il Latte, exhorting ladies to nurse their own
children.]
XI. “From dome to dome when flames infuriate climb,
Sweep the long street, invest the tower sublime;
Gild the tall vanes amid the astonish'd night,
400 And reddening heaven returns the sanguine light;
While with vast strides and bristling hair aloof
Pale Danger glides along the falling roof;
And Giant Terror howling in amaze
Moves his dark limbs across the lurid blaze.
405 NYMPHS! you first taught the gelid wave to rise
Hurl'd in resplendent arches to the skies;
In iron cells condensed the airy spring,
And imp'd the torrent with unfailing wing;
—On the fierce flames the shower impetuous falls,
410 And sudden darkness shrouds the shatter'd walls;
Steam, smoak, and dust in blended volumes roll,
And Night and Silence repossess the Pole.—
[Hurl'd in resplendent arches. l. 406. The addition of an
air-cell to
machines for raising water to extinguish fire was first introduced
by
Mr. Newsham of London, and is now applied to similar engines for
washing
wall-trees in gardens, and to all kinds of forcing pumps, and might
be
applied with advantage to lifting pumps where the water is brought
from
a great distance horizontally. Another kind of machine was invented
by
one Greyl, in which a vessel of water was every way dispersed by
the
explosion of gun-powder lodging in the centre of it, and lighted by
an
adapted match; from this idea Mr. Godfrey proposed a water-bomb of
similar construction. Dr. Hales to prevent the spreading of fire
proposed to cover the floors and stairs of the adjoining houses
with
earth; Mr. Hartley proposed to prevent houses from taking fire by
covering the cieling with thin iron-plates, and Lord Mahon by a bed
of
coarse mortar or plaister between the cieling and floor above it.
May
not this age of chemical science discover some method of injecting
or
soaking timber with lime-water and afterwards with vitriolic acid,
and
thus fill its pores with alabaster? or of penetrating it with
siliceous
matter, by processes similar to those of Bergman and Achard? See
Cronstadt's Mineral. 2d. edit. Vol. I. p. 222.]
“Where were ye, NYMPHS! in those disasterous hours,
Which wrap'd in flames AUGUSTA'S sinking towers?
415 Why did ye linger in your wells and groves,
When sad WOODMASON mourn'd her infant loves?
When thy fair Daughters with unheeded screams,
Ill-fated MOLESWORTH! call'd the loitering streams?—
The trembling Nymph on bloodless fingers hung
420 Eyes from the tottering wall the distant throng,
With ceaseless shrieks her sleeping friends alarms,
Drops with singed hair into her lover's arms.—
The illumin'd Mother seeks with footsteps fleet,
Where hangs the safe balcony o'er the street,
425 Wrap'd in her sheet her youngest hope suspends,
And panting lowers it to her tiptoe friends;
Again she hurries on affection's wings,
And now a third, and now a fourth, she brings;
Safe all her babes, she smooths her horrent brow,
430 And bursts through bickering flames, unscorch'd, below.
So, by her Son arraign'd, with feet unshod
O'er burning bars indignant Emma trod.
[Footnote: Woodmason, Molesworth. l. 416. The histories of
these
unfortunate families may be seen in the Annual Register, or in the
Gentleman's Magazine.]
“E'en on the day when Youth with Beauty wed,
The flames surprized them in their nuptial bed;—
435 Seen at the opening sash with bosom bare,
With wringing hands, and dark dishevel'd hair,
The blushing Beauty with disorder'd charms
Round her fond lover winds her ivory arms;
Beat, as they clasp, their throbbing hearts with fear,
440 And many a kiss is mix'd with many a tear;—
Ah me! in vain the labouring engines pour
Round their pale limbs the ineffectual shower!—
—Then crash'd the floor, while shrinking crouds retire,
And Love and Virtue sunk amid the fire!—
445 With piercing screams afflicted strangers mourn,
And their white ashes mingle in their urn.
XII. “PELLUCID FORMS! whose crystal bosoms show
The shine of welfare, or the shade of woe;
Who with soft lips salute returning Spring,
450 And hail the Zephyr quivering on his wing;
Or watch, untired, the wintery clouds, and share
With streaming eyes my vegetable care;
Go, shove the dim mist from the mountain's brow,
Chase the white fog, which floods the vale below;
455 Melt the thick snows, that linger on the lands,
And catch the hailstones in your little hands;
Guard the coy blossom from the pelting shower,
And dash the rimy spangles from the bower;
From each chill leaf the silvery drops repel,
460 And close the timorous floret's golden bell.
[Shove the dim mist. l. 453. See note on l. 20 of this
Canto.]
[Catch the hail-stones. l. 456. See note on l. 15 of this
Canto.]
[From each chill leaf. l. 459. The upper side of the leaf is
the organ
of vegetable respiration, as explained in the additional notes, No.
XXXVII, hence the leaf is liable to injury from much moisture on
this
surface, and is destroyed by being smeared with oil, in these
respects
resembling the lungs of animals or the spiracula of insects. To
prevent
these injuries some leaves repel the dew-drops from their upper
surfaces
as those of cabbages; other vegetables close the upper surfaces of
their
leaves together in the night or in wet weather, as the sensitive
plant;
others only hang their leaves downwards so as to shoot the wet from
them, as kidney-beans, and many trees. See note on l. 18 of this
Canto.]
[Golden bell. l. 460. There are muscles placed about the
footstalks of
the leaves or leaflets of many plants, for the purpose of closing
their
upper surfaces together, or of bending them down so as to shoot off
the
showers or dew-drops, as mentioned in the preceeding note. The
claws of
the petals or of the divisions of the calyx of many flowers are
furnished in a similar manner with muscles, which are exerted to
open or
close the corol and calyx of the flower as in tragopogon, anemone.
This
action of opening and closing the leaves or flowers does not appear
to
be produced simply by irritation on the muscles themselves,
but by the
connection of those muscles with a sensitive sensorium or
brain
existing in each individual bud or flower. 1st. Because many
flowers
close from the defect of stimulus, not by the excess of it, as by
darkness, which is the absence of the stimulus of light; or by
cold,
which is the absence of the stimulus of heat. Now the defect of
heat, or
the absence of food, or of drink, affects our sensations,
which had
been previously accustomed to a greater quantity of them; but a
muscle
cannot be said to be stimulated into action by a defect of
stimulus. 2.
Because the muscles around the footstalks of the subdivisions of
the
leaves of the sensitive plant are exerted when any injury is
offered to
the other extremity of the leaf, and some of the stamens of the
flowers
of the class Syngenesia contract themselves when others are
irritated.
See note on Chondrilla, Vol. II. of this work.
From this circumstance the contraction of the muscles of vegetables
seems to depend on a disagreeable sensation in some distant
part, and
not on the irritation of the muscles themselves. Thus when a
particle
of dust stimulates the ball of the eye, the eye-lids are instantly
closed, and when too much light pains the retina, the muscles of
the
iris contract its aperture, and this not by any connection or
consent of
the nerves of those parts, but as an effort to prevent or to remove
a
disagreeable sensation, which evinces that vegetables are endued
with
sensation, or that each bud has a common sensorium, and is
furnished
with a brain or a central place where its nerves were connected.]
“So should young SYMPATHY, in female form,
Climb the tall rock, spectatress of the storm;
Life's sinking wrecks with secret sighs deplore,
And bleed for others' woes, Herself on shore;
465 To friendless Virtue, gasping on the strand,
Bare her warm heart, her virgin arms expand,
Charm with kind looks, with tender accents cheer,
And pour the sweet consolatory tear;
Grief's cureless wounds with lenient balms asswage,
470 Or prop with firmer staff the steps of Age;
The lifted arm of mute Despair arrest,
And snatch the dagger pointed to his breast;
Or lull to slumber Envy's haggard mien,
And rob her quiver'd shafts with hand unseen.
475 —Sound, NYMPHS OF HELICON! the trump of Fame,
And teach Hibernian echoes JONES'S name;
Bind round her polish'd brow the civic bay,
And drag the fair Philanthropist to day.—
So from secluded springs, and secret caves,
480 Her Liffy pours his bright meandering waves,
Cools the parch'd vale, the sultry mead divides,
And towns and temples star his shadowy sides.
[Jones's name. l. 476. A young lady who devotes a great part
of an
ample fortune to well chosen acts of secret charity.]
XIII. “CALL YOUR light legions, tread the swampy heath,
Pierce with sharp spades the tremulous peat beneath;
485 With colters bright the rushy sward bisect,
And in new veins the gushing rills direct;—
So flowers shall rise in purple light array'd,
And blossom'd orchards stretch their silver shade;
Admiring glebes their amber ears unfold,
490 And Labour sleep amid the waving gold.
“Thus when young HERCULES with firm disdain
Braved the soft smiles of Pleasure's harlot train;
To valiant toils his forceful limbs assign'd,
And gave to Virtue all his mighty mind,
495 Fierce ACHELOUS rush'd from mountain-caves,
O'er sad Etolia pour'd his wasteful waves,
O'er lowing vales and bleating pastures roll'd,
Swept her red vineyards, and her glebes of gold,
Mined all her towns, uptore her rooted woods,
500 And Famine danced upon the shining floods.
The youthful Hero seized his curled crest,
And dash'd with lifted club the watery Pest;
With waving arm the billowy tumult quell'd,
And to his course the bellowing Fiend repell'd.
[Fierce Achelous. l. 495. The river Achelous deluged Etolia,
by one of
its branches or arms, which in the antient languages are called
horns,
and produced famine throughout a great tract of country, this was
represented in hieroglyphic emblems by the winding course of a
serpent
and the roaring of a bull with large horns. Hercules, or the emblem
of
strength, strangled the serpent, and tore off one horn from the
bull;
that is, he stopped and turned the course of one arm of the river,
and
restored plenty to the country. Whence the antient emblem of the
horn of
plenty. Dict. par M. Danet.]
505 “Then to a Snake the finny Demon turn'd
His lengthen'd form, with scales of silver burn'd;
Lash'd with restless sweep his dragon-train,
And shot meandering o'er the affrighted plain.
The Hero-God, with giant fingers clasp'd
510 Firm round his neck, the hissing monster grasp'd;
With starting eyes, wide throat, and gaping teeth,
Curl his redundant folds, and writhe in death.
“And now a Bull, amid the flying throng
The grisly Demon foam'd, and roar'd along;
515 With silver hoofs the flowery meadows spurn'd,
Roll'd his red eye, his threatening antlers turn'd.
Dragg'd down to earth, the Warrior's victor-hands
Press'd his deep dewlap on the imprinted sands;
Then with quick bound his bended knee he fix'd
520 High on his neck, the branching horns betwixt,
Strain'd his strong arms, his sinewy shoulders bent,
And from his curled brow the twisted terror rent.
—Pleased Fawns and Nymphs with dancing step applaud,
And hang their chaplets round the resting God;
525 Link their soft hands, and rear with pausing toil
The golden trophy on the furrow'd soil;
Fill with ripe fruits, with wreathed flowers adorn,
And give to PLENTY her prolific horn.
[Dragg'd down to earth. l. 517. Described from an antique
gem.]
XIV. “On Spring's fair lap, CERULEAN SISTERS! pour
530 From airy urns the sun-illumined shower,
Feed with the dulcet drops my tender broods,
Mellifluous flowers, and aromatic buds;
Hang from each bending grass and horrent thorn
The tremulous pearl, that glitters to the morn;
535 Or where cold dews their secret channels lave,
And Earth's dark chambers hide the stagnant wave,
O, pierce, YE NYMPHS! her marble veins, and lead
Her gushing fountains to the thirsty mead;
Wide o'er the shining vales, and trickling hills
540 Spread the bright treasure in a thousand rills.
So shall my peopled realms of Leaf and Flower
Exult, inebriate with the genial shower;
Dip their long tresses from the mossy brink,
With tufted roots the glassy currents drink;
545 Shade your cool mansions from meridian beams,
And view their waving honours in your streams.
[Spread the bright treasure. l. 540. The practice of
flooding lands
long in use in China has been but lately introduced into this
country.
Besides the supplying water to the herbage in dryer seasons, it
seems to
defend it from frost in the early part of the year, and thus doubly
advances the vegetation. The waters which rise from springs passing
through marl or limestone are replete with calcareous earth, and
when
thrown over morasses they deposit this earth and incrust or
consolidate
the morass. This kind of earth is deposited in great quantity from
the
springs at Matlock bath, and supplies the soft porous limestone of
which
the houses and walls are there constructed; and has formed the
whole
bank for near a mile on that side of the Derwent on which they
stand.
The water of many springs contains much azotic gas, or phlogistic
air,
besides carbonic gas, or fixed air, as that of Buxton and Bath;
this
being set at liberty may more readily contribute to the production
of
nitre by means of the putrescent matters which it is exposed to by
being
spread upon the surface of the land; in the same manner as
frequently
turning over heaps of manure facilitates the nitrous process by
imprisoning atmospheric air in the interstices of the putrescent
materials. Water arising by land-floods brings along with it much
of the
most soluble parts of the manure from the higher lands to the lower
ones. River-water in its clear state and those springs which are
called
soft are less beneficial for the purpose of watering lands, as they
contain less earthy or saline matter; and water from dissolving
snow
from its slow solution brings but little earth along with it, as
may be
seen by the comparative clearness of the water of snow-floods.]
“Thus where the veins their confluent branches bend,
And milky eddies with the purple blend;
The Chyle's white trunk, diverging from its source,
550 Seeks through the vital mass its shining course;
O'er each red cell, and tissued membrane spreads
In living net-work all its branching threads;
Maze within maze its tortuous path pursues,
Winds into glands, inextricable clues;
555 Steals through the stomach's velvet sides, and sips
The silver surges with a thousand lips;
Fills each fine pore, pervades each slender hair,
And drinks salubrious dew-drops from the air.
“Thus when to kneel in Mecca's awful gloom,
560 Or press with pious kiss Medina's tomb,
League after league, through many a lingering day,
Steer the swart Caravans their sultry way;
O'er sandy wastes on gasping camels toil,
Or print with pilgrim-steps the burning soil;
565 If from lone rocks a sparkling rill descend,
O'er the green brink the kneeling nations bend,
Bathe the parch'd lip, and cool the feverish tongue,
And the clear lake reflects the mingled throng.”
The Goddess paused,—the listening bands awhile
570 Still seem to hear, and dwell upon her smile;
Then with soft murmur sweep in lucid trains
Down the green slopes, and o'er the pebbly plains,
To each bright stream on silver sandals glide,
Reflective fountain, and tumultuous tide.
575 So shoot the Spider-broods at breezy dawn
Their glittering net-work o'er the autumnal lawn;
From blade to blade connect with cordage fine
The unbending grass, and live along the line;
Or bathe unwet their oily forms, and dwell
580 With feet repulsive on the dimpling well.
So when the North congeals his watery mass,
Piles high his snows, and floors his seas with glass;
While many a Month, unknown to warmer rays,
Marks its slow chronicle by lunar days;
585 Stout youths and ruddy damsels, sportive train,
Leave the white soil, and rush upon the main;
From isle to isle the moon-bright squadrons stray,
And win in easy curves their graceful way;
On step alternate borne, with balance nice
590 Hang o'er the gliding steel, and hiss along the ice.
Argument of the Fourth Canto.
Address to the Sylphs. I. Trade-winds. Monsoons. N.E. and S.W.
winds.
Land and sea breezes. Irregular winds. 9. II. Production of vital
air
from oxygene and light. The marriage of Cupid and Psyche. 25. III.
1.
Syroc. Simoom. Tornado. 63. 2. Fog. Contagion. Story of Thyrsis and
Aegle. Love and Death. 79. IV. 1. Barometer. Air-pump. 127. 2. Air-
balloon of Mongulfier. Death of Rozier. Icarus. 143. V. Discoveries
of
Dr. Priestley. Evolutions and combinations of pure air. Rape of
Proserpine. 165. VI. Sea-balloons, or houses constructed to move
under
the sea. Death of Mr. Day. Of Mr. Spalding. Of Captain Pierce and
his
Daughters. 195. VII. Sylphs of music. Cecelia singing. Cupid with a
lyre
riding upon a lion. 233. VIII. Destruction of Senacherib's army by
a
pestilential wind. Shadow of Death. 263. IX. 1. Wish to possess the
secret of changing the course of the winds. 305. 2. Monster
devouring
air subdued by Mr. Kirwan. 321. X. 1. Seeds suspended in their
pods.
Stars discovered by Mr. Herschel. Destruction and resuscitation of
all
things. 351. 2. Seeds within seeds, and bulbs within bulbs. Picture
on
the retina of the eye. Concentric strata of the earth. The great
seed.
381. 3. The root, pith, lobes, plume, calyx, coral, sap, blood,
leaves
respire and absorb light. The crocodile in its egg. 409. XI.
Opening of
the flower. The petals, style, anthers, prolific dust.
Transmutation of
the silkworm. 441. XII. 1. Leaf-buds changed into flower-buds by
wounding the bark, or strangulating a part of the branch. 461. 2.
Ingrafting. Aaron's rod pullulates. 477. XIII. 1. Insects on trees.
Humming-bird alarmed by the spider-like apearance of Cyprepedia.
491. 2.
Diseases of vegetables. Scratch on unnealed glass. 511. XIV. 1.
Tender
flowers. Amaryllis, fritillary, erythrina, mimosa, cerea. 523. 2.
Vines.
Oranges. Diana's trees. Kew garden. The royal family. 541. XV.
Offering
to Hygeia. 587. Departure of the Goddess. 629.
THE
ECONOMY OF VEGETATION.
As when at noon in Hybla's fragrant bowers
CACALIA opens all her honey'd flowers;
Contending swarms on bending branches cling,
And nations hover on aurelian wing;
5 So round the GODDESS, ere she speaks, on high
Impatient SYLPHS in gawdy circlets fly;
Quivering in air their painted plumes expand,
And coloured shadows dance upon the land.
[Cacalia opens. l. 2. The importance of the nectarium or
honey-gland
in the vegetable economy is seen from the very complicated
apparatus,
which nature has formed in some flowers for the preservation of
their
honey from insects, as in the aconites or monkshoods; in other
plants
instead of a great apparatus for its protection a greater secretion
of
it is produced that thence a part may be spared to the depredation
of
insects. The cacalia suaveolens produces so much honey that on some
days
it may be smelt at a great distance from the plant. I remember once
counting on one of these plants besides bees of various kinds
without
number, above two hundred painted butterflies, which gave it the
beautiful appearance of being covered with additional flowers.]
I. “SYLPHS! YOUR light troops the tropic Winds confine,
10 And guide their streaming arrows to the Line;
While in warm floods ecliptic breezes rise,
And sink with wings benumb'd in colder skies.
You bid Monsoons on Indian seas reside,
And veer, as moves the sun, their airy tide;
15 While southern gales o'er western oceans roll,
And Eurus steals his ice-winds from the Pole.
Your playful trains, on sultry islands born,
Turn on fantastic toe at eve and morn;
With soft susurrant voice alternate sweep
20 Earth's green pavilions and encircling deep.
OR in itinerant cohorts, borne sublime
On tides of ether, float from clime to clime;
O'er waving Autumn bend your airy ring,
Or waft the fragrant bosom of the Spring.
[The tropic winds. l. 9. See additional notes, No. XXXIII.]
25 II. “When Morn, escorted by the dancing Hours,
O'er the bright plains her dewy lustre showers;
Till from her sable chariot Eve serene
Drops the dark curtain o'er the brilliant scene;
You form with chemic hands the airy surge,
30 Mix with broad vans, with shadowy tridents urge.
SYLPHS! from each sun-bright leaf, that twinkling shakes
O'er Earth's green lap, or shoots amid her lakes,
Your playful bands with simpering lips invite,
And wed the enamour'd OXYGENE to LIGHT.—
35 Round their white necks with fingers interwove,
Cling the fond Pair with unabating love;
Hand link'd in hand on buoyant step they rise,
And soar and glisten in unclouded skies.
Whence in bright floods the VITAL AIR expands,
40 And with concentric spheres involves the lands;
Pervades the swarming seas, and heaving earths,
Where teeming Nature broods her myriad births;
Fills the fine lungs of all that breathe or bud,
Warms the new heart, and dyes the gushing blood;
45 With Life's first spark inspires the organic frame,
And, as it wastes, renews the subtile flame.
[The enamour'd oxygene. l. 34. The common air of the
atmosphere
appears by the analysis of Dr. Priestley and other philosophers to
consist of about three parts of an elastic fluid unfit for
respiration
or combustion, called azote by the French school, and about one
fourth
of pure vital air fit for the support of animal life and of
combustion,
called oxygene. The principal source of the azote is probably from
the
decomposition of all vegetable and animal matters by putrefaction
and
combustion; the principal source of vital air or oxygene is perhaps
from
the decomposition of water in the organs of vegetables by means of
the
sun's light. The difficulty of injecting vegetable vessels seems to
shew
that their perspirative pores are much less than those of animals,
and
that the water which constitutes their perspiration is so divided
at the
time of its exclusion that by means of the sun's light it becomes
decomposed, the inflammable air or hydrogene, which is one of its
constituent parts, being retained to form the oil, resin, wax,
honey,
&c. of the vegetable economy; and the other part, which united with
light or heat becomes vital air or oxygene gas, rises into the
atmosphere and replenishes it with the food of life.
Dr. Priestley has evinced by very ingenious experiments that the
blood
gives out phlogiston, and receives vital air, or oxygene-gas by the
lungs. And Dr. Crawford has shewn that the blood acquires heat from
this
vital air in respiration. There is however still a something more
subtil
than heat, which must be obtained in respiration from the vital
air, a
something which life can not exist a few minutes without, which
seems
necessary to the vegetable as well as to the animal world, and
which as
no organized vessels can confine it, requires perpetually to be
renewed.
See note on Canto I. l. 401.]
“So pure, so soft, with sweet attraction shone
Fair PSYCHE, kneeling at the ethereal throne;
Won with coy smiles the admiring court of Jove,
50 And warm'd the bosom of unconquer'd LOVE.—
Beneath a moving shade of fruits and flowers
Onward they march to HYMEN'S sacred bowers;
With lifted torch he lights the festive train,
Sublime, and leads them in his golden chain;
55 Joins the fond pair, indulgent to their vows,
And hides with mystic veil their blushing brows.
Round their fair forms their mingling arms they fling,
Meet with warm lip, and clasp with rustling wing.—
—Hence plastic Nature, as Oblivion whelms
60 Her fading forms, repeoples all her realms;
Soft Joys disport on purple plumes unfurl'd,
And Love and Beauty rule the willing world.
[Fair Psyche. l. 48. Described from an antient gem on a fine
onyx in
possession of the Duke of Marlborough, of which there is a
beautiful
print in Bryant's Mythol. Vol II. p. 392. And from another antient
gem
of Cupid and Psyche embracing, of which there is a print in
Spence's
Polymetis. p. 82.]
[Repeoples all her realms. l. 60.
Quae mare navigerum et terras frugiferentes
Concelebras; per te quoniam genus omne animantum
Concipitur, visitque exortum lumina folis. Lucret.]
III. 1. “SYLPHS! Your bold myriads on the withering heath
Stay the fell SYROC'S suffocative breath;
65 Arrest SIMOOM in his realms of sand,
The poisoned javelin balanced in his hand;—
Fierce on blue streams he rides the tainted air,
Points his keen eye, and waves his whistling hair;
While, as he turns, the undulating soil
70 Rolls in red waves, and billowy deserts boil.
[Arrest Simoom. l. 65. “At eleven o'clock while we were with
great
pleasure contemplating the rugged tops of Chiggre, where we
expected to
solace ourselves with plenty of good water, Idris cried out with a
loud
voice, “fall upon your faces, for here is the simoom!” I saw from
the
S.E. a haze come in colour like the purple part of a rainbow, but
not so
compressed or thick; it did not occupy twenty yards in breadth, and
was
about twelve feet high from the ground. It was a kind of a blush
upon
the air, and it moved very rapidly, for I scarce could turn to fall
upon
the ground with my head to the northward, when I felt the heat of
its
current plainly upon my face. We all lay flat upon the ground, as
if
dead, till Idris told us it was blown over. The meteor, or purple
haze,
which I saw was indeed passed; but the light air that still blew
was of
heat to threaten suffocation. For my part I found distinctly in my
breast, that I had imbibed a part of it; nor was I free of an
asthmatic
sensation till I had been some months in Italy.” Bruce's Travels.
Vol.
IV. p. 557.
It is difficult to account for the narrow track of this
pestilential
wind, which is said not to exceed twenty yards, and for its small
elevation of twelve feet. A whirlwind will pass forwards, and throw
down
an avenue of trees by its quick revolution as it passes, but
nothing
like a whirling is described as happening in these narrow streams
of
air, and whirlwinds ascend to greater heights. There seems but one
known
manner in which this channel of air could be effected, and that is
by
electricity.
The volcanic origin of these winds is mentioned in the note on
Chunda in
Vol. II. of this work; it must here be added, that Professor Vairo
at
Naples found, that during the eruption of Vesuvius perpendicular
iron
bars were electric; and others have observed suffocating damps to
attend
these eruptions. Ferber's Travels in Italy, p. 133. And lastly,
that a
current of air attends the passage of electric matter, as is seen
in
presenting an electrized point to the flame of a candle. In Mr.
Bruce's
account of this simoom, it was in its course over a quite dry
desert of
sand, (and which was in consequence unable to conduct an electric
stream
into the earth beneath it,) to some moist rocks at but a few miles
distance; and thence would appear to be a stream of electricity
from a
volcano attended with noxious air; and as the bodies of Mr. Bruce
and
his attendants were insulated on the sand, they would not be
sensible of
their increased electricity, as it passed over them; to which it
may be
added, that a sulphurous or suffocating sensation is said to
accompany
flames of lightning, and even strong sparks of artificial
electricity.
In the above account of the simoom, a great redness in the air is
said
to be a certain sign of its approach, which may be occasioned by
the
eruption of flame from a distant volcano in these extensive and
impenetrable deserts of sand. See Note on l. 294 of this Canto.]
You seize TORNADO by his locks of mist,
Burst his dense clouds, his wheeling spires untwist;
Wide o'er the West when borne on headlong gales,
Dark as meridian night, the Monster sails,
75 Howls high in air, and shakes his curled brow,
Lashing with serpent-train the waves below,
Whirls his black arm, the forked lightning flings,
And showers a deluge from his demon-wings.
[Tornado's. l. 71. See additional notes, No. XXXIII.]
2. “SYLPHS! with light shafts YOU pierce the drowsy FOG,
80 That lingering slumbers on the sedge-wove bog,
With webbed feet o'er midnight meadows creeps,
Or flings his hairy limbs on stagnant deeps.
YOU meet CONTAGION issuing from afar,
And dash the baleful conqueror from his car;
85 When, Guest of DEATH! from charnel vaults he steals,
And bathes in human gore his armed wheels.
[On stagnant deeps. l. 82. All contagious miasmata originate
either
from animal bodies, as those of the small pox, or from putrid
morasses;
these latter produce agues in the colder climates, and malignant
fevers
in the warmer ones. The volcanic vapours which cause epidemic
coughs,
are to be ranked amongst poisons, rather than amongst the miasmata,
which produce contagious diseases.]
“Thus when the PLAGUE, upborne on Belgian air,
Look'd through the mist and shook his clotted hair,
O'er shrinking nations steer'd malignant clouds,
90 And rain'd destruction on the gasping crouds.
The beauteous AEGLE felt the venom'd dart,
Slow roll'd her eye, and feebly throbb'd her heart;
Each fervid sigh seem'd shorter than the last,
And starting Friendship shunn'd her, as she pass'd.
95 —With weak unsteady step the fainting Maid
Seeks the cold garden's solitary shade,
Sinks on the pillowy moss her drooping head,
And prints with lifeless limbs her leafy bed.
—On wings of Love her plighted Swain pursues,
100 Shades her from winds, and shelters her from dews,
Extends on tapering poles the canvas roof,
Spreads o'er the straw-wove matt the flaxen woof,
Sweet buds and blossoms on her bolster strows,
And binds his kerchief round her aching brows;
105 Sooths with soft kiss, with tender accents charms,
And clasps the bright Infection in his arms.—
With pale and languid smiles the grateful Fair
Applauds his virtues, and rewards his care;
Mourns with wet cheek her fair companions fled
110 On timorous step, or number'd with the dead;
Calls to its bosom all its scatter'd rays,
And pours on THYRSIS the collected blaze;
Braves the chill night, caressing and caress'd,
And folds her Hero-lover to her breast.—
115 Less bold, LEANDER at the dusky hour
Eyed, as he swam, the far love-lighted tower;
Breasted with struggling arms the tossing wave,
And sunk benighted in the watery grave.
Less bold, TOBIAS claim'd the nuptial bed,
120 Where seven fond Lovers by a Fiend had bled;
And drove, instructed by his Angel-Guide,
The enamour'd Demon from the fatal bride.—
—SYLPHS! while your winnowing pinions fan'd the air,
And shed gay visions o'er the sleeping pair;
125 LOVE round their couch effused his rosy breath,
And with his keener arrows conquer'd DEATH.
[The beauteous Aegle. l. 91. When the plague raged in
Holland in 1636,
a young girl was seized with it, had three carbuncles, and was
removed
to a garden, where her lover, who was betrothed to her, attended
her as
a nurse, and slept with her as his wife. He remained uninfected,
and she
recovered, and was married to him. The story is related by Vinc.
Fabricius in the Misc. Cur. Ann. II. Obs. 188.]
IV. 1. “You charm'd, indulgent SYLPHS! their learned toil,
And crown'd with fame your TORRICELL, and BOYLE;
Taught with sweet smiles, responsive to their prayer,
130 The spring and pressure of the viewless air.
—How up exhausted tubes bright currents flow
Of liquid silver from the lake below,
Weigh the long column of the incumbent skies,
And with the changeful moment fall and rise.
135 —How, as in brazen pumps the pistons move,
The membrane-valve sustains the weight above;
Stroke follows stroke, the gelid vapour falls,
And misty dew-drops dim the crystal walls;
Rare and more rare expands the fluid thin,
140 And Silence dwells with Vacancy within.—
So in the mighty Void with grim delight
Primeval Silence reign'd with ancient Night.
[Torricell and Boyle. l. 128. The pressure of the atmosphere
was
discovered by Torricelli, a disciple of Galileo, who had previously
found that the air had weight. Dr. Hook and M. Du Hamel ascribe the
invention of the air-pump to Mr. Boyle, who however confesses he
had
some hints concerning its construction from De Guerick. The vacancy
at
the summit of the barometer is termed the Torricellian vacuum, and
the
exhausted receiver of an air pump the Boylean vacuum, in honour of
these
two philosophers.
The mist and descending dew which appear at first exhausting the
receiver of an air-pump, are explained in the Phil. Trans. Vol.
LXXVIII.
from the cold produced by the expansion of air. For a thermometer
placed
in the receiver sinks some degrees, and in a very little time, as
soon
as a sufficient quantity of heat can be acquired from the
surrounding
bodies, the dew becomes again taken up. See additional notes, No.
VII.
Mr. Saussure observed on placing his hygrometer in a receiver of an
air-
pump, that though on beginning to exhaust it the air became misty,
and
parted with its moisture, yet the hair of his hygrometer
contracted, and
the instrument pointed to greater dryness. This unexpected
occurrence is
explained by M. Monge (Annales de Chymie, Tom. V.) to depend on the
want
of the usual pressure of the atmosphere to force the aqueous
particles
into the pores of the hair; and M. Saussure supposes, that his
vesicular
vapour requires more time to be redissolved, than is necessary to
dry
the hair of his thermometer. Essais sur l'Hygrom. p. 226. but I
suspect
there is a less hypothetical way of understanding it; when a colder
body
is brought into warm and moist air, (as a bottle of spring-water
for
instance,) a steam is quickly collected on its surface; the
contrary
occurs when a warmer body is brought into cold and damp air, it
continues free from dew so long as it continues warm; for it warms
the
atmosphere around it, and renders it capable of receiving instead
of
parting with moisture. The moment the air becomes rarefied in the
receiver of the air-pump it becomes colder, as appears by the
thermometer, and deposits its vapour; but the hair of Mr.
Saussure's
hygrometer is now warmer than the air in which it is immersed, and
in
consequence becomes dryer than before, by warming the air which
immediately surrounds it, a part of its moisture evaporating along
with
its heat.]
2. “SYLPHS! your soft voices, whispering from the skies,
Bade from low earth the bold MONGULFIER rise;
145 Outstretch'd his buoyant ball with airy spring,
And bore the Sage on levity of wing;—
Where were ye, SYLPHS! when on the ethereal main
Young ROSIERE launch'd, and call'd your aid in vain?
Fair mounts the light balloon, by Zephyr driven,
150 Parts the thin clouds, and sails along the heaven;
Higher and yet higher the expanding bubble flies,
Lights with quick flash, and bursts amid the skies.—
Headlong He rushes through the affrighted air
With limbs distorted, and dishevel'd hair,
155 Whirls round and round, the flying croud alarms,
And DEATH receives him in his sable arms!—
So erst with melting wax and loosen'd strings
Sunk hapless ICARUS on unfaithful wings;
His scatter'd plumage danced upon the wave,
160 And sorrowing Mermaids deck'd his watery grave;
O'er his pale corse their pearly sea-flowers shed,
And strew'd with crimson moss his marble bed;
Struck in their coral towers the pausing bell,
And wide in ocean toll'd his echoing knell.
[Young Rosiere launch'd. l. 148. M. Pilatre du Rosiere with
a M.
Romain rose in a balloon from Boulogne in June 1785, and after
having
been about a mile high for about half an hour the balloon took
fire, and
the two adventurers were dashed to pieces on their fall to the
ground.
Mr. Rosiere was a philosopher of great talents and activity, joined
with
such urbanity and elegance of manners, as conciliated the
affections of
his acquaintance and rendered his misfortune universally lamented.
Annual Register for 1784 and 1785, p. 329.]
[And wide in ocean. l. 164. Denser bodies propagate
vibration or sound
better than rarer ones; if two stones be struck together under the
water, they may be heard a mile or two by any one whose head is
immersed
at that distance, according to an experiment of Dr. Franklin. If
the ear
be applied to one end of a long beam of timber, the stroke of a pin
at
the other end becomes sensible; if a poker be suspended in the
middle of
a garter, each end of which is pressed against the ear, the least
percussions on the poker give great sounds. And I am informed by
laying
the ear on the ground the tread of a horse may be discerned at a
great
distance in the night. The organs of hearing belonging to fish are
for
this reason much less complicated than of quadrupeds, as the fluid
they
are immersed in so much better conveys its vibrations. And it is
probable that some shell-fish which have twisted shells like the
cochlea
and semicircular canals of the ears of men and quadrupeds may have
no
appropriated organ for perceiving the vibrations of the element
they
live in, but may by their spiral form be in a manner all ear.]
165 V. “SYLPHS! YOU, retiring to sequester'd bowers,
Where oft your PRIESTLEY woos your airy powers,
On noiseless step or quivering pinion glide,
As sits the Sage with Science by his side;
To his charm'd eye in gay undress appear,
170 Or pour your secrets on his raptured ear.
How nitrous Gas from iron ingots driven
Drinks with red lips the purest breath of heaven;
How, while Conferva from its tender hair
Gives in bright bubbles empyrean air;
175 The crystal floods phlogistic ores calcine,
And the pure ETHER marries with the MINE.
[Where oft your Priestley. l. 166. The fame of Dr. Priestley
is known
in every part of the earth where science has penetrated. His
various
discoveries respecting the analysis of the atmosphere, and the
production of variety of new airs or gasses, can only be clearly
understood by reading his Experiments on Airs, (3 vols. octavo,
Johnson,
London.) the following are amongst his many discoveries. 1. The
discovery of nitrous and dephlogisticated airs. 2. The exhibition
of the
acids and alkalies in the form of air. 3. Ascertaining the purity
of
respirable air by nitrous air. 4. The restoration of vitiated air
by
vegetation. 5. The influence of light to enable vegetables to yield
pure
air. 6. The conversion by means of light of animal and vegetable
substances, that would otherwise become putrid and offensive, into
nourishment of vegetables. 7. The use of respiration by the blood
parting with phlogiston, and imbibing dephlogisticated air.
The experiments here alluded to are, 1. Concerning the production
of
nitrous gas from dissolving iron and many other metals in nitrous
acid,
which though first discovered by Dr. Hales (Static. Ess. Vol. I. p.
224)
was fully investigated, and applied to the important purpose of
distinguishing the purity of atmospheric air by Dr. Priestley. When
about two measures of common air and one of nitrous gas are mixed
together a red effervescence takes place, and the two airs occupy
about
one fourth less space than was previously occupied by the common
air
alone.
2. Concerning the green substance which grows at the bottom of
reservoirs of water, which Dr. Priestley discovered to yield much
pure
air when the sun shone on it. His method of collecting this air is
by
placing over the green substance, which he believes to be a
vegetable of
the genus conferva, an inverted bell-glass previously filled with
water,
which subsides as the air arises; it has since been found that all
vegetables give up pure air from their leaves, when the sun shines
upon
them, but not in the night, which may be owing to the sleep of the
plant.
3. The third refers to the great quantity of pure air contained in
the
calces of metals. The calces were long known to weigh much more
than the
metallic bodies before calcination, insomuch that 100 pounds of
lead
will produce 112 pounds of minium; the ore of manganese, which is
always
found near the surface of the earth, is replete with pure air,
which is
now used for the purpose of bleaching. Other metals when exposed to
the
atmosphere attract the pure air from it, and become calces by its
combination, as zinc, lead, iron; and increase in weight in
proportion
to the air, which they imbibe.]
“So in Sicilia's ever-blooming shade
When playful PROSERPINE from CERES stray'd,
Led with unwary step her virgin trains
180 O'er Etna's steeps, and Enna's golden plains;
Pluck'd with fair hand the silver-blossom'd bower,
And purpled mead,—herself a fairer flower;
Sudden, unseen amid the twilight glade,
Rush'd gloomy DIS, and seized the trembling maid.—
185 Her starting damsels sprung from mossy seats,
Dropp'd from their gauzy laps the gather'd sweets,
Clung round the struggling Nymph, with piercing cries,
Pursued the chariot, and invoked the skies;—
Pleased as he grasps her in his iron arms,
190 Frights with soft sighs, with tender words alarms,
The wheels descending roll'd in smoky rings,
Infernal Cupids flapp'd their demon wings;
Earth with deep yawn received the Fair, amaz'd,
And far in Night celestial Beauty blaz'd.
[When playful Proserpine. l. 178. The fable of Proserpine's
being
seized by Pluto as she was gathering flowers, is explained by Lord
Bacon
to signify the combination or marriage of etherial spirit with
earthly
materials. Bacon's Works, Vol. V. p. 470. edit. 4to. Lond. 1778.
This
allusion is still more curiously exact, from the late discovery of
pure
air being given up from vegetables, and that then in its unmixed
state
it more readily combines with metallic or inflammable bodies. From
these
fables which were probably taken from antient hieroglyphics there
is
frequently reason to believe that the Egyptians possessed much
chemical
knowledge, which for want of alphabetical writing perished with
their
philosophers.]
195 VI. “Led by the Sage, Lo! Britain's sons shall guide
Huge SEA-BALLOONS beneath the tossing tide;
The diving castles, roof'd with spheric glass,
Ribb'd with strong oak, and barr'd with bolts of brass,
Buoy'd with pure air shall endless tracks pursue,
200 And PRIESTLEY'S hand the vital flood renew.—
Then shall BRITANNIA rule the wealthy realms,
Which Ocean's wide insatiate wave o'erwhelms;
Confine in netted bowers his scaly flocks,
Part his blue plains, and people all his rocks.
205 Deep, in warm waves beneath the Line that roll,
Beneath the shadowy ice-isles of the Pole,
Onward, through bright meandering vales, afar,
Obedient Sharks shall trail her sceptred car,
With harness'd necks the pearly flood disturb,
210 Stretch the silk rein, and champ the silver curb;
Pleased round her triumph wondering Tritons play,
And Seamaids hail her on the watery way.
—Oft shall she weep beneath the crystal waves
O'er shipwreck'd lovers weltering in their graves;
215 Mingling in death the Brave and Good behold
With slaves to glory, and with slaves to gold;
Shrin'd in the deep shall DAY and SPALDING mourn,
Each in his treacherous bell, sepulchral urn!—
Oft o'er thy lovely daughters, hapless PIERCE!
220 Her sighs shall breathe, her sorrows dew their hearse.—
With brow upturn'd to Heaven, “WE WILL NOT PART!”
He cried, and clasp'd them to his aching heart,—
—Dash'd in dread conflict on the rocky grounds,
Crash the mock'd masts, the staggering wreck rebounds;
225 Through gaping seams the rushing deluge swims,
Chills their pale bosoms, bathes their shuddering limbs,
Climbs their white shoulders, buoys their streaming hair,
And the last sea-shriek bellows in the air.—
Each with loud sobs her tender sire caress'd,
230 And gasping strain'd him closer to her breast!—
—Stretch'd on one bier they sleep beneath the brine,
And their white bones with ivory arms intwine!
[Led by the Sage. l. 195. Dr. Priestley's discovery of the
production
of pure air from such variety of substances will probably soon be
applied to the improvement of the diving bell, as the substances
which
contain vital air in immense quantities are of little value as
manganese
and minium. See additional notes, No. XXXIII. In every hundred
weight of
minium there is combined about twelve pounds of pure air, now as
sixty
pounds of water are about a cubic foot, and as air is eight hundred
times lighter than water, five hundred weight of minium will
produce
eight hundred cubic feet of air or about six thousand gallons. Now,
as
this is at least thrice as pure as atmospheric air, a gallon of it
may
be supposed to serve for three minutes respiration for one man. At
present the air can not be set at liberty from minium by vitriolic
acid
without the application of some heat, this is however very likely
soon
to be discovered, and will then enable adventurers to journey
beneath
the ocean in large inverted ships or diving balloons.
Mr. Boyle relates, that Cornelius Drebelle contrived not only a
vessel
to be rowed under water, but also a liquor to be caried in that
vessel,
which would supply the want of fresh air. The vessel was made by
order
of James I. and carried twelve rowers besides passengers. It was
tried
in the river Thames, and one of the persons who was in that
submarine
voyage told the particulars of the experiments to a person who
related
them to Mr. Boyle. Annual Register for 1774, p. 248.]
[Day and Spalding mourn. l. 217. Mr. Day perished in a
diving bell, or
diving boat, of his own construction at Plymouth in June 1774, in
which
he was to have continued for a wager twelve hours one hundred feet
deep
in water, and probably perished from his not possessing all the
hydrostatic knowledge that was necessary. See note on Ulva, Vol.
II. of
this work. See Annual Register for 1774. p. 245.
Mr. Spalding was professionally ingenious in the art of
constructing and
managing the diving bell, and had practised the business many years
with
success. He went down accompanied by one of his young men twice to
view
the wreck of the Imperial East-Indiaman at the Kish bank in
Ireland. On
descending the third time in June, 1783, they remained about an
hour
under water, and had two barrels of air sent down to them, but on
the
signals from below not being again repeated, after a certain time,
they
were drawn up by their assistants and both found dead in the bell.
Annual Register for 1783, p. 206. These two unhappy events may for
a
time check the ardor of adventurers in traversing the bottom of the
ocean, but it is probable in another half century it may be safer
to
travel under the ocean than over it, since Dr. Priestley's
discovery of
procuring pure air in such great abundance from the calces of
metals.]
[Hapless Pierce! l, 219. The Haslewell East-Indiaman,
outward bound,
was wrecked off Seacomb in the isle of Purbec on the 6th of
January,
1786; when Capt. Pierce, the commander, with two young ladies, his
daughters, and the greatest part of the crew and passengers
perished in
the sea. Some of the officers and about seventy seamen escaped with
great difficulty on the rocks, but Capt. Pierce finding it was
impossible to save the lives of the young ladies refused to quit
the
ship, and perished with them.]
“VII. SYLPHS OF NICE EAR! with beating wings you guide
The fine vibrations of the aerial tide;
235 Join in sweet cadences the measured words,
Or stretch and modulate the trembling cords.
You strung to melody the Grecian lyre,
Breathed the rapt song, and fan'd the thought of fire,
Or brought in combinations, deep and clear,
240 Immortal harmony to HANDEL'S ear.—
YOU with soft breath attune the vernal gale,
When breezy evening broods the listening vale;
Or wake the loud tumultuous sounds, that dwell
In Echo's many-toned diurnal shell.
245 YOU melt in dulcet chords, when Zephyr rings
The Eolian Harp, and mingle all its strings;
Or trill in air the soft symphonious chime,
When rapt CECILIA lifts her eye sublime,
Swell, as she breathes, her bosoms rising snow,
250 O'er her white teeth in tuneful accents slow,
Through her fair lips on whispering pinions move,
And form the tender sighs, that kindle love!
“So playful LOVE on Ida's flowery sides
With ribbon-rein the indignant Lion guides;
255 Pleased on his brinded back the lyre he rings,
And shakes delirious rapture from the strings;
Slow as the pausing Monarch stalks along,
Sheaths his retractile claws, and drinks the song;
Soft Nymphs on timid step the triumph view,
260 And listening Fawns with beating hoofs pursue;
With pointed ears the alarmed forest starts,
And Love and Music soften savage hearts.
[Indignant lion guides. l. 254. Described from an antient
gem,
expressive of the combined power of love and music, in the Museum
Florent.]
VIII. “SYLPHS! YOUR bold hosts, when Heaven with justice
dread
Calls the red tempest round the guilty head,
265 Fierce at his nod assume vindictive forms,
And launch from airy cars the vollied storms.—
From Ashur's vales when proud SENACHERIB trod,
Pour'd his swoln heart, defied the living GOD,
Urged with incessant shouts his glittering powers;
270 And JUDAH shook through all her massy towers;
Round her sad altars press'd the prostrate crowd,
Hosts beat their breasts, and suppliant chieftains bow'd;
Loud shrieks of matrons thrill'd the troubled air,
And trembling virgins rent their scatter'd hair;
275 High in the midst the kneeling King adored,
Spread the blaspheming scroll before the Lord,
Raised his pale hands, and breathed his pausing sighs,
And fixed on Heaven his dim imploring eyes,—
“Oh! MIGHTY GOD! amidst thy Seraph-throng
280 “Who sit'st sublime, the Judge of Right and Wrong;
“Thine the wide earth, bright sun, and starry zone,
“That twinkling journey round thy golden throne;
“Thine is the crystal source of life and light,
“And thine the realms of Death's eternal night.
285 “Oh, bend thine ear, thy gracious eye incline,
“Lo! Ashur's King blasphemes thy holy shrine,
“Insults our offerings, and derides our vows,—-
“Oh! strike the diadem from his impious brows,
“Tear from his murderous hand the bloody rod,
290 “And teach the trembling nations, “THOU ART GOD!”—
—SYLPHS! in what dread array with pennons broad
Onward ye floated o'er the ethereal road,
Call'd each dank steam the reeking marsh exhales,
Contagious vapours, and volcanic gales,
295 Gave the soft South with poisonous breath to blow,
And rolled the dreadful whirlwind on the foe!—
Hark! o'er the camp the venom'd tempest sings,
Man falls on Man, on buckler buckler rings;
Groan answers groan, to anguish anguish yields,
300 And DEATH'S loud accents shake the tented fields!
—High rears the Fiend his grinning jaws, and wide
Spans the pale nations with colossal stride,
Waves his broad falchion with uplifted hand,
And his vast shadow darkens all the land.
[Volcanic gales. l. 294. The pestilential winds of the east
are
described by various authors under various denominations; as
harmattan,
samiel, samium, syrocca, kamsin, seravansum. M. de Beauchamp
describes a
remarkable south wind in the deserts about Bagdad, called
seravansum, or
poison-wind; it burns the face, impedes respiration, strips the
trees of
their leaves, and is said to pass on in a streight line, and often
kills
people in six hours. P. Cotte sur la Meteorol. Analytical Review
for
February, 1790. M. Volney says, the hot wind or ramsin seems to
blow at
the season when the sands of the deserts are the hottest; the air
is
then filled with an extreamly subtle dust. Vol. I. p. 61. These
winds
blow in all directions from the deserts; in Egypt the most violent
proceed from the S.S.W. at Mecca from the E. at Surat from the N.
at
Bassora from the N.W. at Bagdad from the W. and in Syria from the
S.E.
On the south of Syria, he adds, where the Jordan flows is a country
of
volcanos; and it is observed that the earthquakes in Syria happen
after
their rainy season, which is also conformable to a similar
observation
made by Dr. Shaw in Barbary. Travels in Egypt, Vol. I. p. 303.
These winds seem all to be of volcanic origin, as before mentioned,
with
this difference, that the Simoom is attended with a stream of
electric
matter; they seem to be in consequence of earthquakes caused by the
monsoon floods, which fall on volcanic fires in Syria, at the same
time
that they inundate the Nile.]
305 IX. 1. “Ethereal cohorts! Essences of Air!
Make the green children of the Spring your care!
Oh, SYLPHS! disclose in this inquiring age
One GOLDEN SECRET to some favour'd sage;
Grant the charm'd talisman, the chain, that binds,
310 Or guides the changeful pinions of the winds!
—No more shall hoary Boreas, issuing forth
With Eurus, lead the tempests of the North;
Rime the pale Dawn, or veil'd in flaky showers
Chill the sweet bosoms of the smiling Hours.
315 By whispering Auster waked shall Zephyr rise,
Meet with soft kiss, and mingle in the skies,
Fan the gay floret, bend the yellow ear,
And rock the uncurtain'd cradle of the year;
Autumn and Spring in lively union blend,
320 And from the skies the Golden Age descend.
[One golden secret. l. 308. The suddenness of the change of
the wind
from N.E. to S.W. seems to shew that it depends on some minute
chemical
cause; which if it was discovered might probably, like other
chemical
causes, be governed by human agency; such as blowing up rocks by
gunpowder, or extracting the lightening from the clouds. If this
could
be accomplished, it would be the most happy discovery that ever has
happened to these northern latitudes, since in this country the
N.E.
winds bring frost, and the S.W. ones are attended with warmth and
moisture; if the inferior currents of air could be kept perpetually
from
the S.W. supplied by new productions of air at the line, or by
superior
currents flowing in a contrary direction, the vegetation of this
country
would be doubled; as in the moist vallies of Africa, which know no
frost; the number of its inhabitants would be increased, and their
lives
prolonged; as great abundance of the aged and infirm of mankind, as
well
as many birds and animals, are destroyed by severe continued frosts
in
this climate.]
2. “Castled on ice, beneath the circling Bear,
A vast CAMELION spits and swallows air;
O'er twelve degrees his ribs gigantic bend,
And many a league his leathern jaws extend;
325 Half-fish, beneath, his scaly volutes spread,
And vegetable plumage crests his head;
Huge fields of air his wrinkled skin receives,
From panting gills, wide lungs, and waving leaves;
Then with dread throes subsides his bloated form,
330 His shriek the thunder, and his sigh the storm.
Oft high in heaven the hissing Demon wins
His towering course, upborne on winnowing fins;
Steers with expanded eye and gaping mouth,
His mass enormous to the affrighted South;
335 Spreads o'er the shuddering Line his shadowy limbs,
And Frost and Famine follow as he swims.—
SYLPHS! round his cloud-built couch your bands array,
And mould the Monster to your gentle sway;
Charm with soft tones, with tender touches check,
340 Bend to your golden yoke his willing neck,
With silver curb his yielding teeth restrain,
And give to KIRWAN'S hand the silken rein.
—Pleased shall the Sage, the dragon-wings between,
Bend o'er discordant climes his eye serene,
345 With Lapland breezes cool Arabian vales,
And call to Hindostan antarctic gales,
Adorn with wreathed ears Kampschatca's brows,
And scatter roses on Zealandic snows,
Earth's wondering Zones the genial seasons share,
350 And nations hail him “MONARCH OF THE AIR.”
[A vast Camelion. l. 322. See additional notes, No. XXXIII.
on the
destruction and reproduction of the atmosphere.]
[To Kirwan's hand. l. 342. Mr. Kirwan has published a
valuable
treatise on the temperature of climates, as a step towards
investigating
the theory of the winds; and has since written some ingenious
papers on
this subject in the Transactions of the Royal Irish Society.]
X. 1. “SYLPHS! as you hover on ethereal wing,
Brood the green children of parturient Spring!—
Where in their bursting cells my Embryons rest,
I charge you guard the vegetable nest;
355 Count with nice eye the myriad SEEDS, that swell
Each vaulted womb of husk, or pod, or shell;
Feed with sweet juices, clothe with downy hair,
Or hang, inshrined, their little orbs in air.
[The myriad seeds. l. 355. Nature would seem to have been
wonderfully
prodigal in the seeds of vegetables, and the spawn of fish; almost
any
one plant, if all its seeds should grow to maturity, would in a few
years alone people the terrestrial globe. Mr. Ray asserts that 101
seeds of tobacco weighed only one grain, and that from one tobacco
plant
the seeds thus calculated amounted to 360,000! The seeds of the
ferns
are by him supposed to exceed a million on a leaf. As the works of
nature are governed by general laws this exuberant reproduction
prevents
the accidental extinction of the species, at the same time that
they
serve for food for the higher orders of animation.
Every seed possesses a reservoir of nutriment designed for the
growth of
the future plant, this consists of starch, mucilage, or oil, within
the
coat of the seed, or of sugar and subacid pulp in the fruits, which
belongs to it.
For the preservation of the immature seed nature has used many
ingenious
methods; some are wrapped in down, as the seeds of the rose, bean,
and
cotton-plant; others are suspended in a large air-vessel, as those
of
the bladder-sena, staphylaea, and pea.]
“So, late descry'd by HERSCHEL'S piercing sight,
360 Hang the bright squadrons of the twinkling Night;
Ten thousand marshall'd stars, a silver zone,
Effuse their blended lustres round her throne;
Suns call to suns, in lucid clouds conspire,
And light exterior skies with golden fire;
365 Resistless rolls the illimitable sphere,
And one great circle forms the unmeasured year.
—Roll on, YE STARS! exult in youthful prime,
Mark with bright curves the printless steps of Time;
Near and more near your beamy cars approach,
370 And lessening orbs on lessening orbs encroach;—
Flowers of the sky! ye too to age must yield,
Frail as your silken sisters of the field!
Star after star from Heaven's high arch shall rush,
Suns sink on suns, and systems systems crush,
375 Headlong, extinct, to one dark centre fall,
And Death and Night and Chaos mingle all!
—Till o'er the wreck, emerging from the storm,
Immortal NATURE lifts her changeful form,
Mounts from her funeral pyre on wings of flame,
380 And soars and shines, another and the same.
[And light exterior. l. 364. I suspect this line is from
Dwight's
Conquest of Canaan, a poem written by a very young man, and which
contains much fine versification.]
[Near and more near. l. 369. From the vacant spaces in some
parts of
the heavens, and the correspondent clusters of stars in their
vicinity,
Mr. Herschel concludes that the nebulae or constellations of fixed
stars
are approaching each other, and must finally coalesce in one mass.
Phil.
Trans. Vol. LXXV.]
[Till o'er the wreck. l. 377. The story of the phenix rising
from its
own ashes with a twinkling star upon its head, seems to have been
an
antient hieroglyphic emblem of the destruction and resuscitation of
all
things.
There is a figure of the great Platonic year with a phenix on his
hand
on the reverse of a medal of Adrian. Spence's Polym. p. 189.]
2. “Lo! on each SEED within its slender rind
Life's golden threads in endless circles wind;
Maze within maze the lucid webs are roll'd,
And, as they burst, the living flame unfold.
385 The pulpy acorn, ere it swells, contains
The Oak's vast branches in its milky veins;
Each ravel'd bud, fine film, and fibre-line
Traced with nice pencil on the small design.
The young Narcissus, in it's bulb compress'd,
390 Cradles a second nestling on its breast;
In whose fine arms a younger embryon lies,
Folds its thin leaves, and shuts its floret-eyes;
Grain within grain successive harvests dwell,
And boundless forests slumber in a shell.
395 —So yon grey precipice, and ivy'd towers,
Long winding meads, and intermingled bowers,
Green files of poplars, o'er the lake that bow,
And glimmering wheel, which rolls and foams below,
In one bright point with nice distinction lie
400 Plan'd on the moving tablet of the eye.
—So, fold on fold, Earth's wavy plains extend,
And, sphere in sphere, its hidden strata bend;—
Incumbent Spring her beamy plumes expands
O'er restless oceans, and impatient lands,
405 With genial lustres warms the mighty ball,
And the GREAT SEED evolves, disclosing ALL;
LIFE buds or breathes from Indus to the Poles,
And the vast surface kindles, as it rolls!
[Maze within maze. l. 383. The elegant appearance on
dissection of the
young tulip in the bulb was first observed by Mariotte and is
mentioned
in the note on tulipa in Vol.II, and was afterwards noticed by Du
Hamel.
Acad. Scien. Lewenhook assures us that in the bud of a currant tree
he
could not only discover the ligneous part but even the berries
themselves, appearing like small grapes. Chamb. Dict. art. Bud. Mr.
Baker says he dissected a seed of trembling grass in which a
perfect
plant appeared with its root, sending forth two branches, from each
of
which several leaves or blades of grass proceeded. Microsc. Vol. I.
p.
252. Mr. Bonnet saw four generations of successive plants in the
bulb of
a hyacinth. Bonnet Corps Organ. Vol. I. p. 103. Haller's Physiol.
Vol.
I. p. 91. In the terminal bud of a horse-chesnut the new flower may
be
seen by the naked eye covered with a mucilaginous down, and the
same in
the bulb of a narcissus, as I this morning observed in several of
them
sent me by Miss —— for that purpose. Sept. 16.
Mr. Ferber speaks of the pleasure he received in observing in the
buds
of Hepatica and pedicularis hirsuta yet lying hid in the earth, and
in
the gems of the shrub daphne mezereon, and at the base of osmunda
lunaria a perfect plant of the future year, discernable in all its
parts
a year before it comes forth, and in the seeds of nymphea nelumbo
the
leaves of the plant were seen so distinctly that the author found
out by
them what plant the seeds belonged to. The same of the seeds of the
tulip tree or liriodendum tulipiferum. Amaen. Aced. Vol. VI.]
[And the great seed. l. 406. Alluding to the [Greek: proton
oon], or
first great egg of the antient philosophy, it had a serpent wrapped
round it emblematical of divine wisdom, an image of it was
afterwards
preserved and worshipped in the temple of Dioscuri, and supposed to
represent the egg of Leda. See a print of it in Bryant's Mythology.
It
was said to have been broken by the horns of the celestial bull,
that
is, it was hatched by the warmth of the Spring. See note on Canto
I. l.
413.]
[And the vast surface. l. 408. L'Organization, le sentiment,
le
movement spontane, la vie, n'existent qu'a la surface de la terre,
et
dans le lieux exposes a la lumiere. Traite de Chymie par M.
Lavoisier,
Tom. I. p. 202.]
3. “Come, YE SOFT SYLPHS! who sport on Latian land,
410 Come, sweet-lip'd Zephyr, and Favonius bland!
Teach the fine SEED, instinct with life, to shoot
On Earth's cold bosom its descending root;
With Pith elastic stretch its rising stem,
Part the twin Lobes, expand the throbbing Gem;
415 Clasp in your airy arms the aspiring Plume,
Fan with your balmy breath its kindling bloom,
Each widening scale and bursting film unfold,
Swell the green cup, and tint the flower with gold;
While in bright veins the silvery Sap ascends,
420 And refluent blood in milky eddies bends;
While, spread in air, the leaves respiring play,
Or drink the golden quintessence of day.
—So from his shell on Delta's shower-less isle
Bursts into life the Monster of the Nile;
425 First in translucent lymph with cobweb-threads
The Brain's fine floating tissue swells, and spreads;
Nerve after nerve the glistening spine descends,
The red Heart dances, the Aorta bends;
Through each new gland the purple current glides,
430 New veins meandering drink the refluent tides;
Edge over edge expands the hardening scale,
And sheaths his slimy skin in silver mail.
—Erewhile, emerging from the brooding sand,
With Tyger-paw He prints the brineless strand,
435 High on the flood with speckled bosom swims,
Helm'd with broad tail, and oar'd with giant limbs;
Rolls his fierce eye-balls, clasps his iron claws,
And champs with gnashing teeth his massy jaws;
Old Nilus sighs along his cane-crown'd shores,
440 And swarthy Memphis trembles and adores.
[Teach the fine seed. l. 411. The seeds in their natural
state fall on
the surface of the earth, and having absorbed some moisture the
root
shoots itself downwards into the earth and the plume rises in air.
Thus
each endeavouring to seek its proper pabulum directed by a
vegetable
irritability similar to that of the lacteal system and to the lungs
in
animals.
The pith seems to push up or elongate the bud by its elasticity,
like
the pith in the callow quills of birds. This medulla Linneus
believes to
consist of a bundle of fibres, which diverging breaks through the
bark
yet gelatinous producing the buds.
The lobes are reservoirs of prepared nutriment for the young seed,
which
is absorbed by its placental vessels, and converted into sugar,
till it
has penetrated with its roots far enough into the earth to extract
sufficient moisture, and has acquired leaves to convert it into
nourishment. In some plants these lobes rise from the earth and
supply
the place of leaves, as in kidney-beans, cucumbers, and hence seem
to
serve both as a placenta to the foetus, and lungs to the young
plant.
During the process of germination the starch of the seed is
converted
into sugar, as is seen in the process of malting barley for the
purpose
of brewing. And is on this account very similar to the digestion of
food
in the stomachs of animals, which converts all their aliment into a
chyle, which consists of mucilage, oil, and sugar; the placentation
of
buds will be spoken of hereafter.]
[The silvery sap. l. 419. See additional notes, No. XXXVI.]
[Or drink the golden. l. 422. Linneus having observed the
great
influence of light on vegetation, imagined that the leaves of
plants
inhaled electric matter from the light with their upper surface.
(System
of Vegetables translated, p. 8.)
The effect of light on plants occasions the actions of the
vegetable
muscles of their leaf-stalks, which turn the upper side of the leaf
to
the light, and which open their calyxes and chorols, according to
the
experiments of Abbe Tessier, who exposed variety of plants in a
cavern
to different quantities of light. Hist. de L'Academie Royal. Ann.
1783.
The sleep or vigilance of plants seems owing to the presence or
absence
of this stimulus. See note on Nimosa, Vol. II.]
XI. “Come, YE SOFT SYLPHS! who fan the Paphian groves,
And bear on sportive wings the callow Loves;
Call with sweet whisper, in each gale that blows,
The slumbering Snow-drop from her long repose;
445 Charm the pale Primrose from her clay-cold bed,
Unveil the bashful Violet's tremulous head;
While from her bud the playful Tulip breaks,
And young Carnations peep with blushing cheeks;
Bid the closed Petals from nocturnal cold
450 The virgin Style in silken curtains fold,
Shake into viewless air the morning dews,
And wave in light their iridescent hues;
While from on high the bursting Anthers trust
To the mild breezes their prolific dust;
455 Or bend in rapture o'er the central Fair,
Love out their hour, and leave their lives in air.
So in his silken sepulchre the Worm,
Warm'd with new life, unfolds his larva-form;
Erewhile aloft in wanton circles moves,
460 And woos on Hymen-wings his velvet loves.
[Love out their hour. l. 456. The vegetable passion of love
is
agreeably seen in the flower of the parnassia, in which the males
alternately approach and recede from the female, and in the flower
of
nigella, or devil in the bush, in which the tall females bend down
to
their dwarf husbands. But I was this morning surprised to observe,
amongst Sir Brooke Boothby's valuable collection of plants at
Ashbourn,
the manifest adultery of several females of the plant Collinsonia,
who
had bent themselves into contact with the males of other flowers of
the
same plant in their vicinity, neglectful of their own. Sept. 16.
See
additional notes, No. XXXVIII.]
[Unfolds his larva-form. l. 458. The flower bursts forth
from its
larva, the herb, naked and perfect like a butterfly from its
chrysolis;
winged with its corol; wing-sheathed by its calyx; consisting alone
of
the organs of reproduction. The males, or stamens, have their
anthers
replete with a prolific powder containing the vivifying fovilla: in
the
females, or pistils, exists the ovary, terminated by the tubular
stigma.
When the anthers burst and shed their bags of dust, the male
fovilla is
received by the prolific lymph of the stigma, and produces the seed
or
egg, which is nourished in the ovary. System of Vegetables
translated
from Linneus by the Lichfield Society, p. 10.]
XII. 1. “If prouder branches with exuberance rude
Point their green gems, their barren shoots protrude;
Wound them, ye SYLPHS! with little knives, or bind
A wiry ringlet round the swelling rind;
465 Bisect with chissel fine the root below,
Or bend to earth the inhospitable bough.
So shall each germ with new prolific power
Delay the leaf-bud, and expand the flower;
Closed in the Style the tender pith shall end,
470 The lengthening Wood in circling Stamens bend;
The smoother Rind its soft embroidery spread
In vaulted Petals o'er their fertile bed;
While the rough Bark, in circling mazes roll'd,
Forms the green Cup with many a wrinkled fold;
475 And each small bud-scale spreads its foliage hard,
Firm round the callow germ, a Floral Guard.
[Wound them, ye Sylphs! l. 463. Mr. Whitmill advised to bind
some of
the most vigorous shoots with strong wire, and even some of the
large
roots; and Mr. Warner cuts, what he calls a wild worm about the
body of
the tree, or scores the bark quite to the wood like a screw with a
sharp
knife. Bradley on Gardening, Vol. II. p. 155. Mr. Fitzgerald
produced
flowers and fruit on wall trees by cutting off a part of the bark.
Phil.
Trans. Ann. 1761. M. Buffon produced the same effect by a straight
bandage put round a branch, Act. Paris, Ann. 1738, and concludes
that an
ingrafted branch bears better from its vessels being compressed by
the
callous.
A compleat cylinder of the bark about an inch in height was cut off
from
the branch of a pear tree against a wall in Mr. Howard's garden at
Lichfield about five years ago, the circumcised part is now not
above
half the diameter of the branch above and below it, yet this branch
has
been full of fruit every year since, when the other branches of the
tree
bore only sparingly. I lately observed that the leaves of this
wounded
branch were smaller and paler, and the fruit less in size, and
ripened
sooner than on the other parts of the tree. Another branch has the
bark
taken off not quite all round with much the same effect.
The theory of this curious vegetable fact has been esteemed
difficult,
but receives great light from the foregoing account of the
individuality
of buds. A flower-bud dies, when it has perfected its seed, like an
annual plant, and hence requires no place on the bark for new roots
to
pass downwards; but on the contrary leaf-buds, as they advance into
shoots, form new buds in the axilla of every leaf, which new buds
require new roots to pass down the bark, and thus thicken as well
as
elongate the branch, now if a wire or string be tied round the
bark,
many of these new roots cannot descend, and thence more of the buds
will
be converted into flower-buds.
It is customary to debark oak-trees in the spring, which are
intended to
be felled in the ensuing autumn; because the bark comes off easier
at
this season, and the sap-wood, or alburnum, is believed to become
harder
and more durable, if the tree remains till the end of summer. The
trees
thus stripped of their bark put forth shoots as usual with acorns
on the
6th 7th and 8th joint, like vines; but in the branches I examined,
the
joints of the debarked trees were much shorter than those of other
oak-
trees; the acorns were more numerous; and no new buds were produced
above the joints which bore acorns. From hence it appears that the
branches of debarked oak-trees produce fewer leaf-buds, and more
flower-
buds, which last circumstance I suppose must depend on their being
sooner or later debarked in the vernal months. And, secondly, that
the
new buds of debarked oak-trees continue to obtain moisture from the
alburnum after the season of the ascent of sap in other vegetables
ceases; which in this unnatural state of the debarked tree may act
as
capillary tubes, like the alburnum of the small debarked cylinder
of a
pear-tree abovementioned; or may continue to act as placental
vessels,
as happens to the animal embryon in cases of superfetation; when
the
fetus continues a month or two in the womb beyond its usual time,
of
which some instances have been recorded, the placenta continues to
supply perhaps the double office both of nutrition and of
respiration.]
[And bend to earth. l. 466. Mr. Hitt in his treatise on
fruit trees
observes that if a vigorous branch of a wall tree be bent to the
horizon, or beneath it, it looses its vigour and becomes a bearing
branch. The theory of this I suppose to depend on the difficulty
with
which the leaf-shoots can protrude the roots necessary for their
new
progeny of buds upwards along the bended branch to the earth
contrary to
their natural habits or powers, whence more flower-shoots are
produced
which do not require new roots to pass along the bark of the bended
branch, but which let their offspring, the seeds, fall upon the
earth
and seek roots for themselves.]
[With new prolific power. l. 467. About Midsummer the new
buds are
formed, but it is believed by some of the Linnean school, that
these
buds may in their early state be either converted into flower-buds
or
leaf-buds according to the vigour of the vegetating branch. Thus if
the
upper part of a branch be cut away, the buds near the extremity of
the
remaining stem, having a greater proportional supply of nutriment,
or
possessing a greater facility of shooting their roots, or absorbent
vessels, down the bark, will become leaf-buds, which might
otherwise
have been flower-buds. And the contrary as explained in note on l.
463.
of this Canto.]
[Closed in the style. l. 469. “I conceive the medulla of a
plant to
consist of a bundle of nervous fibres, and that the propelling
vital
power separates their uppermost extremities. These, diverging,
penetrate
the bark, which is now gelatinous, and become multiplied in the new
gem,
or leaf-bud. The ascending vessels of the bark being thus divided
by the
nervous fibres, which perforate it, and the ascent of its fluids
being
thus impeded, the bark is extended into a leaf. But the flower is
produced, when the protrusion of the medulla is greater than the
retention of the including cortical part; whence the substance of
the
bark is expanded in the calyx; that of the rind, (or interior
bark,) in
the corol; that of the wood in the stamens, that of the medulla in
the
pistil. Vegetation thus terminates in the production of new life,
the
ultimate medullary and cortical fibres being collected in the
seeds.”
Linnei Systema Veget. p. 6. edit. 14.]
2. “Where cruder juices swell the leafy vein,
Stint the young germ, the tender blossom stain;
On each lop'd shoot a softer scion bind,
480 Pith press'd to pith, and rind applied to rind,
So shall the trunk with loftier crest ascend,
And wide in air its happier arms extend;
Nurse the new buds, admire the leaves unknown,
And blushing bend with fruitage not its own.
[Nurse the new buds. l. 483. Mr. Fairchild budded a
passion-tree,
whose leaves were spotted with yellow, into one which bears long
fruit.
The buds did not take, nevertheless in a fortnight yellow spots
began to
shew themselves about three feet above the inoculation, and in a
short
time afterwards yellow spots appeared on a shoot which came out of
the
ground from another part of the plant. Bradley, Vol. II. p. 129.
These
facts are the more curious since from experiments of ingrafting red
currants on black (Ib. Vol. II.) the fruit does not acquire any
change
of flavour, and by many other experiments neither colour nor any
other
change is produced in the fruit ingrafted on other stocks.
There is an apple described in Bradley's work which is said to have
one
side of it a sweet fruit which boils soft, and the other side a
sour
fruit which boils hard, which Mr. Bradley so long ago as the year
1721
ingeniously ascribes to the farina of one of these apples
impregnating
the other, which would seem the more probable if we consider that
each
division of an apple is a separate womb, and may therefore have a
separate impregnation like puppies of different kinds in one
litter. The
same is said to have occurred in oranges and lemons, and grapes of
different colours.]
485 “Thus when in holy triumph Aaron trod,
And offer'd on the shrine his mystic rod;
First a new bark its silken tissue weaves,
New buds emerging widen into leaves;
Fair fruits protrude, enascent flowers expand,
490 And blush and tremble round the living wand.
XIII. 1. “SYLPHS! on each Oak-bud wound the wormy galls,
With pigmy spears, or crush the venom'd balls;
Fright the green Locust from his foamy bed,
Unweave the Caterpillar's gluey thread;
495 Chase the fierce Earwig, scare the bloated Toad,
Arrest the snail upon his slimy road;
Arm with sharp thorns the Sweet-brier's tender wood,
And dash the Cynips from her damask bud;
Steep in ambrosial dews the Woodbine's bells,
500 And drive the Night-moth from her honey'd cells.
So where the Humming-bird in Chili's bowers
On murmuring pinions robs the pendent flowers;
Seeks, where fine pores their dulcet balm distill,
And sucks the treasure with proboscis-bill;
505 Fair CYPREPEDIA with successful guile
Knits her smooth brow, extinguishes her smile;
A Spiders bloated paunch and jointed arms
Hide her fine form, and mask her blushing charms;
In ambush sly the mimic warrior lies,
510 And on quick wing the panting plunderer flies.
[Fair Cyprepedia. l. 505. The cyprepedium from South America
is
supposed to be of larger size and brighter colours than that from
North
America from which this print is taken; it has a large globular
nectary
about the size of a pidgeon's egg of a fleshy colour, and an
incision or
depression on its upper part, much resembling the body of the large
American spider; this globular nectary is attached to divergent
slender
petals not unlike the legs of the same animal. This spider is
called by
Linneus Arenea avicularia, with a convex orbicular thorax, the
center
transversely excavated, he adds that it catches small birds as well
as
insects, and has the venemous bite of a serpent. System Nature,
Tom. I.
p. 1034. M. Lonvilliers de Poincy, (Histoire Nat. des Antilles,
Cap.
xiv. art. III.) calls it Phalange, and describes the body to be the
size
of a pidgeon's egg, with a hollow on its back like a navel, and
mentions
its catching the humming-bird in its strong nets.
The similitude of this flower to this great spider seems to be a
vegetable contrivance to prevent the humming-bird from plundering
its
honey. About Matlock in Derbyshire the fly-ophris is produced, the
nectary of which so much resembles the small wall-bee, perhaps the
apis
ichneumonea, that it may be easily mistaken for it at a small
distance.
It is probable that by this means it may often escape being
plundered.
See note on lonicera in the next poem.
A bird of our own country called a willow-wren (Motacilla) runs up
the
stem of the crown-imperial (Frittillaria coronalis) and sips the
pendulous drops within its petals. This species of Motacilla is
called
by Ray Regulus non cristatus. White's Hist. of Selborne.]
[Illustration: Cypripedium. London, Published Dec'r 1st 1791 by
J.
Johnson, St. Paul's Church Yard.]
2. “Shield the young Harvest from devouring blight,
The Smut's dark poison, and the Mildew white;
Deep-rooted Mould, and Ergot's horn uncouth,
And break the Canker's desolating tooth.
515 First in one point the festering wound confin'd
Mines unperceived beneath the shrivel'd rin'd;
Then climbs the branches with increasing strength,
Spreads as they spread, and lengthens with their length;
—Thus the slight wound ingraved on glass unneal'd
520 Runs in white lines along the lucid field;
Crack follows crack, to laws elastic just,
And the frail fabric shivers into dust.
[Shield the young harvest. l. 511. Linneus enumerates but
four
diseases of plants; Erysyche, the white mucor or mould, with
sessile
tawny heads, with which the leaves are sprinkled, as is frequent on
the
hop, humulus, maple, acer, &c. Rubigo, the ferrugineous powder
sprinkled
under the leaves frequent in lady's mantle, alchemilla, &c.
Clavus, when the seeds grow out into larger horns black without, as
in
rye. This is called Ergot by the french writers.
Ustulago, when the fruit instead of seed produces a black powder,
as in
barley, oats, &c. To which perhaps the honey-dew ought to have been
added, and the canker, in the former of which the nourishing fluid
of
the plant seems to be exsuded by a retrograde motion of the
cutaneous
lymphatics, as in the sweating sickness of the last century. The
latter
is a phagedenic ulcer of the bark, very destructive to young apple-
trees, and which in cherry-trees is attended with a deposition of
gum
arabic, which often terminates in the death of the tree.]
[Ergot's horn. l. 513. There is a disease frequently affects
the rye
in France, and sometimes in England in moist seasons, which is
called
Ergot, or horn seed; the grain becomes considerably elongated and
is
either straight or crooked, containing black meal along with the
white,
and appears to be pierced by insects, which were probably the cause
of
the disease. Mr. Duhamel ascribes it to this cause, and compares it
to
galls on oak-leaves. By the use of this bad grain amongst the poor
diseases have been produced attended with great debility and
mortification of the extremities both in France and England. Dict.
Raison. art. Siegle. Philosop. Transact.]
[On glass unneal'd. l. 519. The glass makers occasionally
make what
they call proofs, which are cooled hastily, whereas the
other glass
vessels are removed from warmer ovens to cooler ones, and suffered
to
cool by slow degrees, which is called annealing, or nealing them.
If an
unnealed glass be scratched by even a grain of sand falling into
it, it
will seem to consider of it for some time, or even a day, and will
then
crack into a thousand pieces.
The same happens to a smooth surfaced lead-ore in Derbyshire, the
workmen having cleared a large face of it scratch it with picks,
and in
a few hours many tons of it crack to pieces and fall, with a kind
of
explosion. Whitehurst's Theory of Earth.
Glass dropped into cold water, called Prince Rupert's drops,
explode
when a small part of their tails are broken off, more suddenly
indeed,
but probably from the same cause. Are the internal particles of
these
elastic bodies kept so far from each other by the external crust
that
they are nearly in a state of repulsion into which state they are
thrown
by their vibrations from any violence applied? Or, like elastic
balls in
certain proportions suspended in contact with each other, can
motion
once began be increased by their elasticity, till the whole
explodes?
And can this power be applied to any mechanical purposes?]
XIV. I. “SYLPHS! if with morn destructive Eurus springs,
O, clasp the Harebel with your velvet wings;
525 Screen with thick leaves the Jasmine as it blows,
And shake the white rime from the shuddering Rose;
Whilst Amaryllis turns with graceful ease
Her blushing beauties, and eludes the breeze.—
SYLPHS! if at noon the Fritillary droops,
530 With drops nectareous hang her nodding cups;
Thin clouds of Gossamer in air display,
And hide the vale's chaste Lily from the ray;
Whilst Erythrina o'er her tender flower
Bends all her leaves, and braves the sultry hour;—
535 Shield, when cold Hesper sheds his dewy light,
Mimosa's soft sensations from the night;
Fold her thin foilage, close her timid flowers,
And with ambrosial slumbers guard her bowers;
O'er each warm wall while Cerea flings her arms,
540 And wastes on night's dull eye a blaze of charms.
[Illustration: Erythrina Corallodendron. London Published Dec'r
1st by
J. Johnson St. Paul's Church Yard.]
[With ambrosial slumbers. l. 538. Many vegetables during the
night do
not seem to respire, but to sleep like the dormant animals and
insects
in winter. This appears from the mimosa and many other plants
closing
the upper sides of their leaves together in their sleep, and thus
precluding that side of them from both light and air. And from many
flowers closing up the polished or interior side of their petals,
which
we have also endeavoured to shew to be a respiratory organ.
The irritability of plants is abundantly evinced by the absorption
and
pulmonary circulation of their juices; their sensibility is shewn
by the
approaches of the males to the females, and of the females to the
males
in numerous instances; and, as the essential circumstance of sleep
consists in the temporary abolition of voluntary power alone, the
sleep
of plants evinces that they possess voluntary power; which also
indisputably appears in many of them by closing their petals or
their
leaves during cold, or rain, or darkness, or from mechanic
violence.]
2. Round her tall Elm with dewy fingers twine
The gadding tendrils of the adventurous Vine;
From arm to arm in gay festoons suspend
Her fragrant flowers, her graceful foliage bend;
545 Swell with sweet juice her vermil orbs, and feed
Shrined in transparent pulp her pearly seed;
Hang round the Orange all her silver bells,
And guard her fragrance with Hesperian spells;
Bud after bud her polish'd leaves unfold,
550 And load her branches with successive gold.
So the learn'd Alchemist exulting sees
Rise in his bright matrass DIANA'S trees;
Drop after drop, with just delay he pours
The red-fumed acid on Potosi's ores;
555 With sudden flash the fierce bullitions rise,
And wide in air the gas phlogistic flies;
Slow shoot, at length, in many a brilliant mass
Metallic roots across the netted glass;
Branch after branch extend their silver stems,
560 Bud into gold, and blossoms into gems.
[Diana's trees, l. 552. The chemists and astronomers from
the earliest
antiquity have used the same characters to represent the metals and
the
planets, which were most probably outlines or abstracts of the
original
hieroglyphic figures of Egypt. These afterwards acquired niches in
their
temples, and represented Gods as well as metals and planets; whence
silver is called Diana, or the moon, in the books of alchemy.
The process for making Diana's silver tree is thus described by
Lemeri.
Dissolve one ounce of pure silver in acid of nitre very pure and
moderately strong; mix this solution with about twenty ounces of
distilled water; add to this two ounces of mercury, and let it
remain at
rest. In about four days there will form upon the mercury a tree of
silver with branches imitating vegetation.
1. As the mercury has a greater affinity than silver with the
nitrous
acid, the silver becomes precipitated; and, being deprived of the
nitrous oxygene by the mercury, sinks down in its metallic form and
lustre. 2. The attraction between silver and mercury, which causes
them
readily to amalgamate together, occasions the precipitated silver
to
adhere to the surface of the mercury in preference to any other
part of
the vessel. 3. The attraction of the particles of the precipitated
silver to each other causes the beginning branches to thicken and
elongate into trees and shrubs rooted on the mercury. For other
circumstances concerning this beautiful experiment see Mr. Keir's
Chemical Dictionary, art. Arbor Dianae; a work perhaps of greater
utility to mankind than the lost Alexandrian Library; the
continuation
of which is so eagerly expected by all, who are occupied in the
arts, or
attached to the sciences.]
So sits enthron'd in vegetable pride
Imperial KEW by Thames's glittering side;
Obedient sails from realms unfurrow'd bring
For her the unnam'd progeny of spring;
565 Attendant Nymphs her dulcet mandates hear,
And nurse in fostering arms the tender year,
Plant the young bulb, inhume the living seed,
Prop the weak stem, the erring tendril lead;
Or fan in glass-built fanes the stranger flowers
570 With milder gales, and steep with warmer showers.
Delighted Thames through tropic umbrage glides,
And flowers antarctic, bending o'er his tides;
Drinks the new tints, the sweets unknown inhales,
And calls the sons of science to his vales.
575 In one bright point admiring Nature eyes
The fruits and foliage of discordant skies,
Twines the gay floret with the fragrant bough,
And bends the wreath round GEORGE'S royal brow.
—Sometimes retiring, from the public weal
580 One tranquil hour the ROYAL PARTNERS steal;
Through glades exotic pass with step sublime,
Or mark the growths of Britain's happier clime;
With beauty blossom'd, and with virtue blaz'd,
Mark the fair Scions, that themselves have rais'd;
585 Sweet blooms the Rose, the towering Oak expands,
The Grace and Guard of Britain's golden lands.
XV. SYLPHS! who, round earth on purple pinions borne,
Attend the radiant chariot of the morn;
Lead the gay hours along the ethereal hight,
590 And on each dun meridian shower the light;
SYLPHS! who from realms of equatorial day
To climes, that shudder in the polar ray,
From zone to zone pursue on shifting wing,
The bright perennial journey of the spring;
595 Bring my rich Balms from Mecca's hallow'd glades,
Sweet flowers, that glitter in Arabia's shades;
Fruits, whose fair forms in bright succession glow
Gilding the Banks of Arno, or of Po;
Each leaf, whose fragrant steam with ruby lip
600 Gay China's nymphs from pictur'd vases sip;
Each spicy rind, which sultry India boasts,
Scenting the night-air round her breezy coasts;
Roots whose bold stems in bleak Siberia blow,
And gem with many a tint the eternal snow;
605 Barks, whose broad umbrage high in ether waves
O'er Ande's steeps, and hides his golden caves;
—And, where yon oak extends his dusky shoots
Wide o'er the rill, that bubbles from his roots;
Beneath whose arms, protected from the storm
610 A turf-built altar rears it's rustic form;
SYLPHS! with religious hands fresh garlands twine,
And deck with lavish pomp HYGEIA'S shrine.
“Call with loud voice the Sisterhood, that dwell
On floating cloud, wide wave, or bubbling well;
615 Stamp with charm'd foot, convoke the alarmed Gnomes
From golden beds, and adamantine domes;
Each from her sphere with beckoning arm invite,
Curl'd with red flame, the Vestal Forms of light.
Close all your spotted wings, in lucid ranks
620 Press with your bending knees the crowded banks,
Cross your meek arms, incline your wreathed brows,
And win the Goddess with unwearied vows.
“Oh, wave, HYGEIA! o'er BRITANNIA'S throne
Thy serpent-wand, and mark it for thy own;
625 Lead round her breezy coasts thy guardian trains,
Her nodding forests, and her waving plains;
Shed o'er her peopled realms thy beamy smile,
And with thy airy temple crown her isle!”
The GODDESS ceased,—and calling from afar
630 The wandering Zephyrs, joins them to her car;
Mounts with light bound, and graceful, as she bends,
Whirls the long lash, the flexile rein extends;
On whispering wheels the silver axle slides,
Climbs into air, and cleaves the crystal tides;
635 Burst from its pearly chains, her amber hair
Streams o'er her ivory shoulders, buoy'd in air;
Swells her white veil, with ruby clasp confined
Round her fair brow, and undulates behind;
The lessening coursers rise in spiral rings,
640 Pierce the slow-sailing clouds, and stretch their shadowy
wings.
CONTENTS
OF
THE NOTES.
CANTO I.
Rosicrucian machinery. 73
All bodies are immersed in the matter of heat. Particles of bodies
do
not touch each other. 97
Gradual progress of the formation of the earth, and of plants and
animals. Monstrous births 101
Fixed stars approach towards each other, they were projected from
chaos
by explosion, and the planets projected from them 105
An atmosphere of inflammable air above the common atmosphere
principally
about the poles 123
Twilight fifty miles high. Wants further observations 126
Immediate cause of volcanos from steam and other vapours. They
prevent
greater earthquakes 152
Conductors of heat. Cold on the tops of mountains 176
Phosphorescent light in the evening from all bodies 177
Phosphoric light from calcined shells. Bolognian stone. Experiments
of
Beccari and Wilson 182
Ignis fatuus doubtful 189
Electric Eel. Its electric organs. Compared to the electric Leyden
phial
202
Discovery of fire. Tools of steel. Forests subdued. Quantity of
food
increased by cookery 212
Medusa originally an hieroglyphic of divine wisdom 218
Cause of explosions from combined heat. Heat given out from air in
respiration. Oxygene looses less heat when converted into nitrous
acid
than in any other of its combinations 226
Sparks from the collision of flints are electric. From the
collision of
flint and steel are from the combustion of the steel 229
Gunpowder described by Bacon. Its power. Should be lighted in the
centre. A new kind of it. Levels the weak and strong 242
Steam-engine invented by Savery. Improved by Newcomen. Perfected by
Watt
and Boulton 254
Divine benevolence. The parts of nature not of equal excellence 278
Mr. Boulton's steam-engine for the purpose of coining would save
many
lives from the executioner 281
Labours of Hercules of great antiquity. Pillars of Hercules.
Surface of
the Mediteranean lower than the Atlantic. Abyla and Calpe. Flood of
Deucalion 297
Accumulation of electricity not from friction 335
Mr. Bennet's sensible electrometer 345
Halo of saints is pictorial language 358
We have a sense adapted to perceive heat but not electricity 365
Paralytic limbs move by electric influence 367
Death of Professor Richman by electricity 373
Lightning drawn from the clouds. How to be safe in thunder storms
383
Animal heat from air in respiration. Perpetual necessity of
respiration.
Spirit of animation perpetually renewed 401
Cupid rises from the egg of night. Mrs. Cosway's painting of this
subject 413
Western-winds. Their origin. Warmer than south-winds. Produce a
thaw
430
Water expands in freezing. Destroys succulent plants, not resinous
ones.
Trees in valleys more liable to injury. Fig-trees bent to the
ground in
winter 439
Buds and bulbs are the winter cradle of the plant. Defended from
frost
and from insects. Tulip produces one flower-bulb and several
leaf-bulbs,
and perishes. 460
Matter of heat is different from light. Vegetables blanched by
exclusion
of light. Turn the upper surface of their leaves to the light.
Water
decomposed as it escapes from their pores. Hence vegetables purify
air
in the day time only. 462
Electricity forwards the growth of plants. Silk-worms electrised
spin
sooner. Water decomposed in vegetables, and by electricity 463
Sympathetic inks which appear by heat, and disappear in the cold.
Made
from cobalt 487
Star in Cassiope's chair 515
Ice-islands 100 fathoms deep. Sea-ice more difficult of solution.
Ice
evaporates producing great cold. Ice-islands increase. Should be
navigated into southern climates. Some ice-islands have floated
southwards 60 miles long. Steam attending them in warm climates 529
Monsoon cools the sands of Abyssinia 547
Ascending vapours are electrised plus, as appears from an
experiment of
Mr. Bennet. Electricity supports vapour in clouds. Thunder showers
from
combination of inflammable and vital airs 553
CANTO II.
Solar volcanos analogous to terrestrial and lunar ones. Spots of
the sun
are excavations 14
Spherical form of the earth. Ocean from condensed vapour. Character
of
Mr. Whitehurst 17
Granite the oldest part of the earth. Then limestone. And lastly,
clay,
iron, coal, sandstone. Three great concentric divisions of the
globe
35
Formation of primeval islands before the production of the moon.
Paradise. The Golden Age. Rain-bow. Water of the sea originally
fresh
36
Venus rising from the sea an hieroglyphic emblem of the production
of
the earth beneath the ocean 47
First great volcanos in the central parts of the earth. From steam,
inflammable gas, and vital air. Present volcanos like mole-hills 68
Moon has little or no atmosphere. Its ocean is frozen. Is not yet
inhabited, but may be in time 82
Earth's axis changed by the ascent of the moon. Its diurnal motion
retarded. One great tide 84
Limestone produced from shells. Spars with double refractions.
Marble.
Chalk 93
Antient statues of Hercules. Antinous. Apollo. Venus. Designs of
Roubiliac. Monument of General Wade. Statues of Mrs. Damer 101
Morasses rest on limestone. Of immense extent 116
Salts from animal and vegetable bodies decompose each other, except
marine salt. Salt mines in Poland. Timber does not decay in them.
Rock-
salt produced by evaporation from sea-water. Fossil shells in salt
mines. Salt in hollow pyramids. In cubes. Sea-water contains about
one-
thirtieth of salt 119
Nitre, native in Bengal and Italy. Nitrous gas combined with vital
air
produces red clouds, and the two airs occupy less space than one of
them
before, and give out heat. Oxygene and azote produce nitrous acid
143
Iron from decomposed vegetables. Chalybeat springs. Fern-leaves in
nodules of iron. Concentric spheres of iron nodules owing to
polarity,
like iron-filings arranged by a magnet. Great strata of the earth
owing
to their polarity 183
Hardness of steel for tools. Gave superiority to the European
nations.
Welding of steel. Its magnetism. Uses of gold 192
Artificial magnets improved by Savery and Dr. Knight, perfected by
Mr.
Michel. How produced. Polarity owing to the earth's rotatory
motion. The
electric fluid, and the matter of heat, and magnetism gravitate on
each
other. Magnetism being the lightest is found nearest the axis of
the
motion. Electricity produces northern lights by its centrifugal
motion
193
Acids from vegetable recrements. Flint has its acid from the new
world.
Its base in part from the old world, and in part from the new.
Precious
stones 215
Diamond. Its great refraction of light. Its volatibility by heat.
If an
inflammable body. 228
Fires of the new world from fermentation. Whence sulphur and
bitumen by
sublimation, the clay, coal, and flint remaining 275
Colours not distinguishable in the enamel-kiln, till a bit of dry
wood
is introduced 283
Etrurian pottery prior to the foundations of Rome. Excelled in fine
forms, and in a non-vitreous encaustic painting, which was lost
till
restored by Mr. Wedgwood. Still influences the taste of the
inhabitants
291
Mr. Wedgwood's cameo of a slave in chains, and of Hope 315
Basso-relievos of two or more colours not made by the antients.
Invented
by Mr. Wedgwood 342
Petroleum and naptha have been sublimed. Whence jet and amber. They
absorb air. Attract straws when rubbed. Electricity from electron
the
greek name for amber 353
Clefts in granite rocks in which metals are found. Iron and
manganese
found in all vegetables. Manganese in limestone. Warm springs from
steam
rising up the clefts of granite and limestone. Ponderous earth in
limestone clefts and in granite. Copper, lead, iron, from
descending
materials. High mountains of granite contain no ores near their
summits.
Transmutation of metals. Of lead into calamy. Into silver 398
Armies of Cambytes destroyed by famine, and by sand-storms 435
Whirling turrets of sand described and explained 478
Granite shews iron as it decomposes. Marble decomposes. Immense
quantity
of charcoal exists in limestone. Volcanic slags decompose, and
become
clay 523
Millstones raised by wooden pegs 524
Hannibal made a passage by fire over the Alps 534
Passed tense of many words twofold, as driven or drove, spoken or
spoke.
A poetic licence 609
CANTO III.
Clouds consist of aqueous spheres, which do not easily unite, like
globules of quicksilver, as may be seen in riding through water.
Owing
to electricity. Snow. Hailstones rounded by attrition and
dissolution of
their angles. Not from frozen drops of water 15
Dew on points and edges of grass, or hangs over cabbage-leaves,
needle
floats on water 18
Mists over rivers and on mountains. Halo round the moon. Shadow of
a
church-steeple upon a mist. Dry mist, or want of transparency of
the
air, a sign of fair-weather 20
Tides on both sides of the earth. Moon's tides should be much
greater
than the earth's tides. The ocean of the moon is frozen 61
Spiral form of shells saves calcareous matter. Serves them as an
organ
of hearing. Calcareous matter produced from inflamed membranes.
Colours
of shells, labradore-stone from mother-pearl. Fossil shells not now
found recent 66
Sea-insects like flowers. Actinia 82
Production of pearls, not a disease of the fish. Crab's eyes.
Reservoirs
of pearly matter 84
Rocks of coral in the south-sea. Coralloid limestone at Linsel, and
Coalbrook Dale 90
Rocks thrown from mountains, ice from glaciers, and portions of
earth,
or morasses, removed by columns of water. Earth-motion in
Shropshire.
Water of wells rising above the level of the ground. St. Alkmond's
well
near Derby might be raised many yards, so as to serve the town.
Well at
Sheerness, and at Hartford in Connecticut 116
Moonsoons attended with rain Overflowing of the Nile. Vortex of
ascending air. Rising of the Dogstar announces the floods of the
Nile.
Anubis hung out upon their temples 129
Situations exempt from rain. At the Line in Lower Egypt. On the
coast of
Peru 138
Giesar, a boiling fountain in Iceland. Water with great degrees of
heat
dissolves siliceous matter. Earthquake from steam 150
Warm springs not from decomposed pyrites. From steam rising up
fissures
from great depths 166
Buxton bath possesses 82 degrees of heat. Is improperly called a
warm
bath. A chill at immersion, and then a sensation of warmth, like
the eye
in an obscure room owing to increased sensibility of the skin 184
Water compounded of pure air and inflammable air with as much
matter of
heat as preserves it fluid. Perpetually decomposed by vegetables in
the
sun's light, and recomposed in the atmosphere 204
Mythological interpretation of Jupiter and Juno designed as an
emblem of
the composition of water from two airs 260
Death of Mrs. French 308
Tomb of Mr. Brindley 341
Invention of the pump. The piston lifts the atmosphere above it.
The
surrounding atmosphere presses up the water into the vacuum. Manner
in
which a child sucks 366
Air-cell in engines for extinguishing fire. Water dispersed by the
explosion of Gunpowder. Houses preserved from fire by earth on the
floors, by a second ceiling of iron-plates or coarse mortar. Wood
impregnated with alabaster or flint 406
Muscular actions and sensations of plants 460
River Achelous. Horn of Plenty 495
Flooding lands defends them from vernal frosts. Some springs
deposit
calcareous earth. Some contain azotic gas, which contributes to
produce
nitre. Snow water less serviceable 540
CANTO IV.
Cacalia produces much honey, that a part may be taken by insects
without
injury 2
Analysis of common air. Source of azote. Of Oxygene. Water
decomposed by
vegetable pores and the sun's light. Blood gives out phlogiston and
receives vital air. Acquires heat and the vivifying principle 34
Cupid and Psyche 48
Simoom, a pestilential wind. Described. Owing to volcanic
electricity.
Not a whirlwind 65
Contagion either animal or vegetable 82
Thyrsis escapes the Plague 91
Barometer and air-pump, Dew on exhausting the receiver though the
hygrometer points to dryness. Rare air will dissolve or acquire
more
heat, and more moisture, and more electricity 128
Sound propagated best by dense bodies, as wood, and water, and
earth.
Fish in spiral shells all ear 164
Discoveries of Dr. Priestley. Green vegetable matter. Pure air
contained
in the calces of metals, as minium, manganese, calamy, ochre 166
Fable of Proserpine an antient chemical emblem 178
Diving balloons supplied with pure air from minium. Account of one
by
Mr. Boyle 195
Mr. Day. Mr. Spalding 217
Captain Pierce and his daughters 219
Pestilential winds of volcanic origin. Jordan flows through a
country of
volcanos 294
Change of wind owing to small causes. If the wind could be
governed, the
products of the earth would be doubled, and its number of
inhabitants
increased 308
Mr. Kirwan's treatise on temperature of climates 342
Seeds of plants. Spawn of fish. Nutriment lodged in seeds. Their
preservation in their seed-vessels 355
Fixed stars approach each other 369
Fable of the Phoenix 377
Plants visible within bulbs, and buds, and seeds 383
Great Egg of Night 406
Seeds shoot into the ground. Pith. Seed-lobes. Starch converted
into
sugar. Like animal chyle 411
Light occasions the actions of vegetable muscles. Keeps them awake
422
Vegetable love in Parnassia, Nigella. Vegetable adultery in
Collinsonia
456
Strong vegetable shoots and roots bound with wire, in part
debarked,
whence leaf-buds converted into flower-buds. Theory of this curious
fact
463
Branches bent to the horizon bear more fruit 466
Engrafting of a spotted passion-flower produced spots upon the
stock.
Apple soft on one side and hard on the other 483
Cyprepedium assumes the form of a large spider to affright the
humming-
bird. Fly-ophris. Willow-wren sucks the honey of the crown-imperial
505
Diseases of plants four kinds. Honey-dew 511
Ergot a disease of rye 513
Glass unannealed. Its cracks owing to elasticity. One kind of
lead-ore
cracks into pieces. Prince Rupert's drops. Elastic balls 519
Sleep of plants. Their irritability, sensibility, and voluntary
motions
538
ADDITIONAL NOTES.
Etherial Forms! you chase the shooting stars,
Or yoke the vollied lightnings to your cars.
CANTO I. l. 115.
There seem to be three concentric strata of our incumbent
atmosphere; in
which, or between them, are produced four kinds of meteors;
lightning,
shooting stars, fire-balls, and northern lights. First, the lower
region
of air, or that which is dense enough to resist by the adhesion of
its
particles the descent of condensed vapour, or clouds, which may
extend
from one to three or four miles high. In this region the common
lightning is produced from the accumulation or defect of electric
matter
in those floating fields of vapour either in respect to each other,
or
in respect to the earth beneath them, or the dissolved vapour above
them, which is constantly varying both with the change of the form
of
the clouds, which thus evolve a greater or less surface; and also
with
their ever-changing degree of condensation. As the lightning is
thus
produced in dense air, it proceeds but a short course on account of
the
greater resistance which it encounters, is attended with a loud
explosion, and appears with a red light.
2. The second region of the atmosphere I suppose to be that which
has
too little tenacity to support condensed vapour or clouds; but
which yet
contains invisible vapour, or water in aerial solution. This aerial
solution of water differs from that dissolved in the matter of
heat, as
it is supported by its adhesion to the particles of air, and is not
precipitated by cold. In this stratum it seems probable that the
meteors
called shooting stars are produced; and that they consist of
electric
sparks, or lightning, passing from one region to another of these
invisible fields of aero-aqueous solution. The height of these
shooting
stars has not yet been ascertained by sufficient observation; Dr.
Blagden thinks their situation is lower down in the atmosphere than
that
of fireballs, which he conjectures from their swift apparent
motion, and
ascribes their smallness to the more minute division of the
electric
matter of which they are supposed to consist, owing to the greater
resistance of the denser medium through which they pass, than that
in
which the fire-balls exist. Mr. Brydone observed that the shooting
stars
appeared to him to be as high in the atmosphere, when he was near
the
summit of mount Etna, as they do when observed from the plain.
Phil.
Tran. Vol. LXIII.
As the stratum of air, in which shooting stars are supposed to
exist is
much rarer than that in which lightning resides, and yet much
denser
than that in which fire-balls are produced, they will be attracted
at a
greater distance than the former, and at a less than the latter.
From
this rarity of the air so small a sound will be produced by their
explosion, as not to reach the lower parts of the atmosphere; their
quantity of light from their greater distance being small, is never
seen
through dense air at all, and thence does not appear red, like
lightning
or fire balls. There are no apparent clouds to emit or to attract
them,
because the constituent parts of these aero-aqueous regions may
possess
an abundance or deficiency of electric matter and yet be in perfect
reciprocal solution. And lastly their apparent train of light is
probably owing only to a continuance of their impression on the
eye; as
when a fire-stick is whirled in the dark it gives the appearance of
a
compleat circle of fire: for these white trains of shooting stars
quickly vanish, and do not seem to set any thing on fire in their
passage, as seems to happen in the transit of fire-balls.
3. The second region or stratum of air terminates I suppose where
the
twilight ceases to be refracted, that is, where the air is 3000
times
rarer than at the surface of the earth; and where it seems probable
that
the common air ends, and is surrounded by an atmosphere of
inflammable
gas tenfold rarer than itself. In this region I believe fire-balls
sometimes to pass, and at other times the northern lights to exist.
One
of these fire-balls or draco volans, was observed by Dr. Pringle
and
many others on Nov. 26, 1758, which was afterwards estimated to
have
been a mile and a half in circumference, to have been about one
hundred
miles high, and to have moved towards the north with a velocity of
near
thirty miles in a second of time. This meteor had a real tail many
miles
long, which threw off sparks in its course, and the whole exploded
with
a sound like distant thunder. Philos. Trans. Vol. LI.
Dr. Blagden has related the history of another large meteor, or
fire-
ball, which was seen the 18th of August, 1783, with many ingenious
observations and conjectures. This was estimated to be between 60
and 70
miles high, and to travel 1000 miles at the rate of about twenty
miles
in a second. This fire-ball had likewise a real train of light left
behind it in its passage, which varied in colour; and in some part
of
its course gave off sparks or explosions where it had been
brightest;
and a dusky red streak remained visible perhaps a minute. Philos.
Trans.
Vol. LXXIV.
These fire-balls differ from lightning, and from shooting stars in
many
remarkable circumstances; as their very great bulk, being a mile
and a
half in diameter; their travelling 1000 miles nearly horizontally;
their
throwing off sparks in their passage; and changing colours from
bright
blue to dusky red; and leaving a train of fire behind them,
continuing
about a minute. They differ from the northern lights in not being
diffused, but passing from one point of the heavens to another in a
defined line; and this in a region above the crepuscular
atmosphere,
where the air is 3000 tines rarer than at the surface of the earth.
There has not yet been even a conjecture which can account for
these
appearances!—One I shall therefore hazard; which, if it does not
inform, may amuse the reader.
In the note on l. 123, it was shewn that there is probably a
supernatant
stratum of inflammable gas or hydrogene, over the common
atmosphere; and
whose density at the surface where they meet, must be at least ten
times
less than that upon which it swims; like chemical ether floating
upon
water, and perhaps without any real contact. 1. In this region,
where
the aerial atmosphere terminates and the inflammable one begins,
the
quantity of tenacity or resistance must be almost inconceivable; in
which a ball of electricity might pass 1000 miles with greater ease
than
through a thousandth part of an inch of glass. 2. Such a ball of
electricity passing between inflammable and common air would set
fire to
them in a line as it patted along; which would differ in colour
according to the greater proportionate commixture of the two airs;
and
from the same cause there might occur greater degrees of
inflammation,
or branches of fire, in some parts of its course.
As these fire-balls travel in a defined line, it is pretty evident
from
the known laws of electricity, that they must be attracted; and as
they
are a mile or more in diameter, they must be emitted from a large
surface of electric matter; because large nobs give larger sparks,
less
diffused, and more brightly luminous, than less ones or points, and
resist more forceably the emission of the electric matter. What is
there
in nature can attract them at so great a distance as 1000 miles,
and so
forceably as to detach an electric spark of a mile diameter? Can
volcanos at the time of their eruptions have this effect, as they
are
generally attended with lightning? Future observations must
discover
these secret operations of nature! As a stream of common air is
carried
along with the passage of electric aura from one body to another;
it is
easy to conceive, that the common air and the inflammable air
between
which the fire-ball is supposed to pass, will be partially
intermixed by
being thus agitated, and so far as it becomes intermixed it will
take
fire, and produce the linear flame and branching sparks above
described.
In this circumstance of their being attracted, and thence passing
in a
defined line, the fire-balls seem to differ from the coruscations
of the
aurora borealis, or northern lights, which probably take place in
the
same region of the atmosphere; where the common air exists in
extreme
tenuity, and is covered by a still rarer sphere of inflammable gas,
ten
times lighter than itself.
As the electric streams, which constitute these northern lights,
seem to
be repelled or radiated from an accumulation of that fluid in the
north,
and not attracted like the fireballs; this accounts for the
diffusion of
their light, as well as the silence of their passage; while their
variety of colours, and the permanency of them, and even the
breadth of
them in different places, may depend on their setting on fire the
mixture of inflammable and common air through which they pass; as
seems
to happen in the transit of the fire-balls.
It was observed by Dr. Priestley that the electric shock taken
through
inflammable air was red, in common air it is blueish; to these
circumstances perhaps some of the colours of the northern lights
may
bear analogy; though the density of the medium through which light
is
seen must principally vary its colour, as is well explained by Mr.
Morgan. Phil. Trans. Vol. LXXV. Hence lightning is red when seen
through
a dark cloud, or near the horizon; because the more refrangible
rays
cannot permeate so dense a medium. But the shooting stars consist
of
white light, as they are generally seen on clear nights, and nearly
vertical: in other situations their light is probably too faint to
come
to us. But as in some remarkable appearances of the northern
lights, as
in March, 1716, all the prismatic colours were seen quickly to
succeed
each other, these appear to have been owing to real combustion; as
the
density of the interposed medium could not be supposed to change so
frequently; and therefore these colours must have been owing to
different degrees of heat according to Mr. Morgan's theory of
combustion. In Smith's Optics, p. 69. the prismatic colours, and
optical
deceptions of the northern lights are described by Mr. Cotes.
The Torricellian vacuum, if perfectly free from air, is said by Mr.
Morgan and others to be a perfect non-conductor. This circumstance
therefore would preclude the electric streams from rising above the
atmosphere. But as Mr. Morgan did not try to pass an electric shock
through a vacuum, and as air, or something containing air,
surrounding
the transit of electricity may be necessary to the production of
light,
the conclusion may perhaps still be dubious. If however the streams
of
the northern lights were supposed to rise above our atmosphere,
they
would only be visible at each extremity of their course; where they
emerge from, or are again immerged into the atmosphere; but not in
their
journey through the vacuum; for the absence of electric light in a
vacuum is sufficiently proved by the common experiment of shaking a
barometer in the dark; the electricity, produced by the friction of
the
mercury in the glass at its top, is luminous if the barometer has a
little air in it; but there is no light if the vacuum be complete.
The aurora borealis, or northern dawn, is very ingeniously
accounted for
by Dr. Franklin on principles of electricity. He premises the
following
electric phenomena: 1. that all new fallen snow has much positive
electricity standing on its surface. 2. That about twelve degrees
of
latitude round the poles are covered with a crust of eternal ice,
which
is impervious to the electric fluid. 3. That the dense part of the
atmosphere rises but a few miles high; and that in the rarer parts
of it
the electric fluid will pass to almost any distance.
Hence he supposes there must be a great accumulation of positive
electric matter on the fresh fallen snow in the polar regions;
which,
not being able to pass through the crust of ice into the earth,
must
rise into the rare air of the upper parts of our atmosphere, which
will
the least resist its passage; and passing towards the equator
descend
again into the denser atmosphere, and thence into the earth in
silent
streams. And that many of the appearances attending these lights
are
optical deceptions, owing to the situation of the eye that beholds
them;
which makes all ascending parallel lines appear to converge to a
point.
The idea, above explained in note on l. 123, of the existence of a
sphere of inflammable gas over the aerial atmosphere would much
favour
this theory of Dr. Franklin; because in that case the dense aerial
atmosphere would rise a much less height in the polar regions,
diminishing almost to nothing at the pole itself; and thus give an
easier passage to the ascent of the electric fluid. And from the
great
difference in the specific gravity of the two airs, and the
velocity of
the earth's rotation, there must be a place between the poles and
the
equator, where the superior atmosphere of inflammable gas would
terminate; which would account for these streams of the aurora
borealis
not appearing near the equator; add to this that it is probable the
electric fluid may be heavier than the magnetic one; and will
thence by
the rotation of the earth's surface ascend over the magnetic one by
its
centrifugal force; and may thus be induced to rise through the thin
stratum of aerial atmosphere over the poles. See note on Canto II.
l.
193. I shall have occasion again to mention this great accumulation
of
inflammable air over the poles; and to conjecture that these
northern
lights may be produced by the union of inflammable with common air,
without the assistance of the electric spark to throw them into
combustion.
The antiquity of the appearance of northern lights has been
doubted; as
none were recorded in our annals since the remarkable one on Nov.
14,
1574, till another remarkable one on March 6, 1716, and the three
following nights, which were seen at the same time in Ireland,
Russia,
and Poland, extending near 30 degrees of longitude and from about
the
50th degree of latitude over almost all the north of Europe. There
is
however reason to believe them of remote antiquity though
inaccurately
described; thus the following curious passage from the Book of
Maccabees, (B. II. c. v.) is such a description of them, as might
probably be given by an ignorant and alarmed people. “Through all
the
city, for the space of almost forty days, there were seen horsemen
running in the air, in cloth of gold, and armed with lances, like a
band
of soldiers; and troops of horsemen in array encountering and
running
one against another, with shaking of shields and multitude of
pikes, and
drawing of swords, and casting of darts, and glittering of golden
ornaments and harness.”
Cling round the aerial bow with prisms bright,
And pleased untwist the sevenfold threads of light.
CANTO I. l. 117.
The manner in which the rainbow is produced was in some measure
understood before Sir Isaac Newton had discovered his theory of
colours.
The first person who expressly shewed the rainbow to be formed by
the
reflection of the sunbeams from drops of falling rain was Antonio
de
Dominis. This was afterwards more fully and distinctly explained by
Des
Cartes. But what caused the diversity of its colours was not then
understood; it was reserved for the immortal Newton to discover
that the
rays of light consisted of seven combined colours of different
refrangibility, which could be seperated at pleasure by a wedge of
glass. Pemberton's View of Newton.
Sir Isaac Newton discovered that the prismatic spectrum was
composed of
seven colours in the following proportions, violet 80, indigo 40,
blue
60, green 60, yellow 48, orange 27, red 45. If all these colours be
painted on a circular card in the proportions above mentioned, and
the
card be rapidly whirled on its center, they produce in the eye the
sensation of white. And any one of these colours may be imitated by
painting a card with the two colours which are contiguous to it, in
the
same proportions as in the spectrum, and whirling them in the same
manner. My ingenious friend, Mr. Galton of Birmingham, ascertained
in
this manner by a set of experiments the following propositions; the
truth of which he had preconceived from the above data.
1. Any colour in the prismatic spectrum may be imitated by a
mixture of
the two colours contiguous to it.
2. If any three successive colours in the prismatic spectrum are
mixed,
they compose only the second or middlemost colour.
3. If any four succesive colours in the prismatic spectrum be
mixed, a
tint similar to a mixture of the second and third colours will be
produced, but not precisely the same, because they are not in the
same
proportion.
4. If beginning with any colour in the circular spectrum, you take
of
the second colour a quantity equal to the first, second, and third;
and
add to that the fifth colour, equal in quantity to the fourth,
fifth,
and sixth; and with these combine the seventh colour in the
proportion
it exists in the spectrum, white will be produced. Because the
first,
second, and third, compose only the second; and the fourth, fifth,
and
sixth, compose only the fifth; therefore if the seventh be added,
the
same effect is produced, as if all the seven were employed.
5. Beginning with any colour in the circular spectrum, if you take
a
tint composed of a certain proportion of the second and third,
(equal in
quantity to the first, second, third, and fourth,) and add to this
the
sixth colour equal in quantity to the fifth, sixth, and seventh,
white
will be produced.
From these curious experiments of Mr. Galton many phenomena in the
chemical changes of colours may probably become better understood;
especially if, as I suppose, the same theory must apply to
transmitted
colours, as to reflected ones. Thus it is well known, that if the
glass
of mangonese, which is a tint probably composed of violet and
indigo, be
mixed in a certain proportion with the glass of lead, which is
yellow;
that the mixture becomes transparent. Now from Mr. Galton's
experiments
it appears, that in reflected colours such a mixture would produce
white, that is, the same as if all the colours were reflected. And
therefore in transmitted colours the same circumstances must
produce
transparency, that is, the same as if all the colours were
transmitted.
For the particles, which constitute the glass of mangonese will
transmit
red, violet, indigo, and blue; and those of the glass of lead will
transmit orange, yellow, and green; hence all the primary colours
by a
mixture of these glasses become transmitted, that is, the glass
becomes
transparent.
Mr. Galton has further observed that five successive prismatic
colours
may be combined in such proportions as to produce but one colour, a
circumstance which might be of consequence in the art of painting.
For
if you begin at any part of the circular spectrum above described,
and
take the first, second, and third colours in the proportions in
which
they exist in the spectrum; these will compose only the second
colour
equal in quantity to the first, second, and third; add to these the
third, fourth, and fifth in the proportion they exist in the
spectrum,
and these will produce the fourth colour equal in quantity to the
third,
fourth, and fifth. Consequently this is precisely the same thing,
as
mixing the second and fourth colours only; which mixture would only
produce the third colour. Therefore if you combine the first,
second,
fourth, and fifth in the proportions in which they exist in the
spectrum, with double the quantity of the third colour, this third
colour will be produced. It is probable that many of the unexpected
changes in mixing colours on a painter's easle, as well as in more
fluid
chemical mixtures, may depend on these principles rather than on a
new
arrangement or combination of their minute particles.
Mr. Galton further observes, that white may universally be produced
by
the combination of one prismatic colour, and a tint intermediate to
two
others. Which tint may be distinguished by a name compounded of the
two
colours, to which it is intermediate. Thus white is produced by a
mixture of red with blue-green. Of orange with indigo-blue. Of
Yellow
with violet-indigo. Of green with red-violet. Of blue with
Orange-red.
Of indigo with yellow-orange. Of violet with green-yellow. Which he
further remarks exactly coincides with the theory and facts
mentioned by
Dr. Robert Darwin of Shrewsbury in his account of ocular spectra;
who
has shewn that when one of these contrasted colours has been long
viewed, a spectrum or appearance of the other becomes visible in
the
fatigued eye. Philos. Trans. Vol. LXXVI. for the year 1786.
These experiments of Mr. Galton might much assist the copper-plate
printers of callicoes and papers in colours; as three colours or
more
might be produced by two copper-plates. Thus suppose some yellow
figures
were put on by the first plate, and upon some parts of these yellow
figures and on other parts of the ground blue was laid on by
another
copper-plate. The three colours of yellow, blue, and green might be
produced; as green leaves with yellow and blue flowers.
Eve's silken couch with gorgeous tints adorn,
Or fire the arrowy throne of rising morn.
CANTO I. l. 119.
The rays from the rising and setting sun are refracted by our
spherical
atmosphere, hence the most refrangible rays, as the violet, indigo,
and
blue are reflected in greater quantities from the morning and
evening
skies; and the least refrangible ones, as red and orange, are last
seen
about the setting sun. Hence Mr. Beguelin observed that the shadow
of
his finger on his pocket-book was much bluer in the morning and
evening,
when the shadow was about eight times as long as the body from
which it
was projected. Mr. Melville observes, that the blue rays being more
refrangible are bent down in the evenings by our atmosphere, while
the
red and orange being less refrangible continue to pass on and tinge
the
morning and evening clouds with their colours. See Priestley's
History
of Light and Colours, p. 440. But as the particles of air, like
those of
water, are themselves blue, a blue shadow may be seen at all times
of
the day, though much more beautifully in the mornings and evenings,
or
by means of a candle in the middle of the day. For if a shadow on a
piece of white paper is produced by placing your finger between the
paper and a candle in the day light, the shadow will appear very
blue;
the yellow light of the candle upon the other parts of the paper
apparently deepens the blue by its contrast; these colours being
opposite to each other, as explained in note II.
Colours are produced from clouds or mists by refraction, as well as
by
reflection. In riding in the night over an unequal country I
observed a
very beautiful coloured halo round the moon, whenever I was covered
with
a few feet of mist, as I ascended from the vallies; which ceased to
appear when I rose above the mist. This I suppose was owing to the
thinness of the stratum of mist, in which I was immersed; had it
been
thicker, the colours refracted by the small drops, of which a fog
consists, would not have passed through it down to my eye.
There is a bright spot seen on the cornea of the eye, when we face
a
window, which is much attended to by portrait painters; this is the
light reflected from the spherical surface of the polished cornea,
and
brought to a focus; if the observer is placed in this focus, he
sees the
image of the window; if he is placed before or behind the focus, he
only
sees a luminous spot, which is more luminous and of less extent,
the
nearer he approaches to the focus. The luminous appearance of the
eyes
of animals in the dusky corners of a room, or in holes in the
earth, may
arise in some instances from the same principle; viz. the
reflection of
the light from the spherical cornea; which will be coloured red or
blue
in some degree by the morning, evening, or meridian light; or by
the
objects from which that light is previously reflected. In the
cavern at
Colebrook Dale, where the mineral tar exsudes, the eyes of the
horse,
which was drawing a cart from within towards the mouth of it,
appeared
like two balls of phosphorus, when he was above 100 yards off, and
for a
long time before any other part of the animal was visible. In this
case
I suspect the luminous appearance to have been owing to the light,
which
had entered the eye, being reflected from the back surface of the
vitreous humour, and thence emerging again in parallel rays from
the
animals eye, as it does from the back surface of the drops of the
rainbow, and from the water-drops which lie, perhaps without
contact, on
cabbage-leaves, and have the brilliancy of quicksilver. This
accounts
for this luminous appearance being best seen in those animals which
have
large apertures in their iris, as in cats and horses, and is the
only
part visible in obscure places, because this is a better reflecting
surface than any other part of the animal. If any of these emergent
rays
from the animals eye can be supposed to have been reflected from
the
choroid coat through the semi-transparent retina, this would
account for
the coloured glare of the eyes of dogs or cats and rabits in dark
corners.
Alarm with comet-blaze the sapphire plain,
The wan stars glimmering through its silver train.
CANTO I. l. 133.
There have been many theories invented to account for the tails of
comets. Sir Isaac Newton thinks that they consist of rare vapours
raised
from the nucleus of the comet, and so rarefied by the sun's heat as
to
have their general gravitation diminished, and that they in
consequence
ascend opposite to the sun, and from thence reflect the rays of
light.
Dr. Halley compares the light of the tails of comets to the streams
of
the aurora borealis, and other electric effluvia. Philos. Trans.
No.
347.
Dr. Hamilton observes that the light of small stars are seen
undiminished through both the light of the tails of comets, and of
the
aurora borealis, and has further illustrated their electric
analogy, and
adds that the tails of comets consist of a lucid self-shining
substance
which has not the power of refracting or reflecting the rays of
light.
Essays.
The tail of the comet of 1744 at one time appeared to extend above
16
degrees from its body, and must have thence been above twenty three
millions of miles long. And the comet of 1680, according to the
calculations of Dr. Halley on November the 11th, was not above one
semi-
diameter of the earth, or less than 4000 miles to the northward of
the
way of the earth; at which time had the earth been in that part of
its
orbit, what might have been the consequence! no one would probably
have
survived to have registered the tremendous effects.
The comet of 1531, 1607, and 1682 having returned in the year 1759,
according to Dr. Halley's prediction in the Philos. Trans. for
1705,
there seems no reason to doubt that all the other comets will
return
after their proper periods. Astronomers have in general acquiesced
in
the conjecture of Dr. Halley, that the comets of 1532, and 1661 are
one
and the same comet, from the similarity of the elements of their
orbits,
and were therefore induced to expect its return to its perihelium
1789.
As this comet is liable to be disturbed in its ascent from the sun
by
the planets Jupiter and Saturn, Dr. Maskelyne expected its return
to its
perihelium in the beginning of the year 1789, or the latter end of
the
year 1788, and certainly sometime before the 27th of April, 1789,
which
prediction has not been fulfilled. Phil. Trans. Vol. LXXVI.
Or give the sun's phlogistic orb to roll.
CANTO I. l. 136.
The dispute among philosophers about phlogiston is not concerning
the
existence of an inflammable principle, but rather whether there be
one
or more inflammable principles. The disciples of Stahl, which till
lately included the whole chemical world, believed in the identity
of
phlogiston in all bodies which would flame or calcine. The
disciples of
Lavoisier pay homage to a plurality of phlogistons under the
various
names of charcoal, sulphur, metals, &c. Whatever will unite with
pure
air, and thence compose an acid, is esteemed in this ingenious
theory to
be a different kind of phlogistic or inflammable body. At the same
time
there remains a doubt whether these inflammable bodies, as metals,
sulphur, charcoal, &c. may not be compounded of the same phlogiston
along with some other material yet undiscovered, and thus an unity
of
phlogiston exist, as in the theory of Stahl, though very
differently
applied in the explication of chemical phenomena.
Some modern philosophers are of opinion that the sun is the great
fountain from which the earth and other planets derive all the
phlogiston which they possess; and that this is formed by the
combination of the solar rays with all opake bodies, but
particularly
with the leaves of vegetables, which they suppose to be organs
adapted
to absorb them. And that as animals receive their nourishment from
vegetables they also obtain in a secondary manner their phlogiston
from
the sun. And lastly as great masses of the mineral kingdom, which
have
been found in the thin crust of the earth which human labour has
penetrated, have evidently been formed from the recrements of
animal and
vegetable bodies, these also are supposed thus to have derived
their
phlogiston from the sun.
Another opinion concerning the sun's rays is, that they are not
luminous
till they arrive at our atmosphere; and that there uniting with
some
part of the air they produce combustion, and light is emitted, and
that
an etherial acid, yet undiscovered, is formed from this combustion.
The more probable opinion is perhaps, that the sun is a phlogistic
mass
of matter, whose surface is in a state of combustion, which like
other
burning bodies emits light with immense velocity in all directions;
that
these rays of light act upon all opake bodies, and combining with
them
either displace or produce their elementary heat, and become
chemically
combined with the phlogistic part of them; for light is given out
when
phlogistic bodies unite with the oxygenous principle of the air, as
in
combustion, or in the reduction of metallic calxes; thus in
presenting
to the flame of a candle a letter-wafer, (if it be coloured with
red-
lead,) at the time the red-lead becomes a metallic drop, a flash of
light is perceived. Dr. Alexander Wilson very ingeniously
endeavours to
prove that the sun is only in a state of combustion on its surface,
and
that the dark spots seen on the disk are excavations or caverns
through
the luminous crust, some of which are 4000 miles in diameter. Phil.
Trans. 1774. Of this I shall have occasion to speak again.
Round her still centre tread the burning soil,
And watch the billowy Lavas, as they boil.
CANTO I. l. 139.
M. de Mairan in a paper published in the Histoire de l'Academie de
Sciences, 1765, has endeavoured to shew that the earth receives but
a
small part of the heat which it possesses, from the sun's rays, but
is
principally heated by fires within itself. He thinks the sun is the
cause of the vicissitudes of our seasons of summer and winter by a
very
small quantity of heat in addition to that already residing in the
earth, which by emanations from the centre to the circumference
renders
the surface habitable, and without which, though the sun was
constantly
to illuminate two thirds of the globe at once, with a heat equal to
that
at the equator, it would soon become a mass of solid ice. His
reasonings
and calculations on this subject are too long and too intricate to
be
inserted here, but are equally curious and ingenious and carry much
conviction along with them.
The opinion that the center of the earth consists of a large mass
of
burning lava, has been espoused by Boyle, Boerhave, and many other
philosophers. Some of whom considering its supposed effects on
vegetation and the formation of minerals have called it a second
sun.
There are many arguments in support of this opinion, 1. Because the
power of the sun does not extend much beyond ten feet deep into the
earth, all below being in winter and summer always of the same
degree of
heat, viz. 48, which being much warmer than the mildest frost, is
supposed to be sustained by some internal distant fire. Add to this
however that from experiments made some years ago by Dr. Franklin
the
spring-water at Philadelphia appeared to be of 52 deg. of heat,
which seems
further to confirm this opinion, since the climates in North
America are
supposed to be colder than those of Europe under similar degrees of
latitude. 2. Mr. De Luc in going 1359 feet perpendicular into the
mines
of Hartz on July the 5th, 1778, on a very fine day found the air at
the
bottom a little warmer than at the top of the shaft. Phil. Trans.
Vol.
LXIX. p. 488. In the mines in Hungary, which are 500 cubits deep,
the
heat becomes very troublesome when the miners get below 480 feet
depth.
Morinus de Locis subter. p. 131. But as some other deep
mines as
mentioned by Mr. Kirwan are said to possess but the common heat of
the
earth; and as the crust of the globe thus penetrated by human
labour is
so thin compared with the whole, no certain deduction can be made
from
these facts on either side of the question. 3. The warm-springs in
many
parts of the earth at great distance from any Volcanos seem to
originate
from the condensation of vapours arising from water which is boiled
by
subterraneous fires, and cooled again in their passage through a
certain
length of the colder soil; for the theory of chemical solution will
not
explain the equality of their heat at all seasons and through so
many
centuries. See note on Fucus in Vol. II. See a letter on this
subject in
Mr. Pilkinton's View of Derbyshire from Dr. Darwin. 4. From the
situations of volcanos which are always found upon the summit of
the
highest mountains. For as these mountains have been lifted up and
lose
several of their uppermost strata as they rise, the lowest strata
of the
earth yet known appear at the tops of the highest hills; and the
beds of
the Volcanos upon these hills must in consequence belong to the
lowest
strata of the earth, consisting perhaps of granite or basaltes,
which
were produced before the existance of animal or vegetable bodies,
and
might constitute the original nucleus of the earth, which I have
supposed to have been projected from the sun, hence the volcanos
themselves appear to be spiracula or chimneys belonging to great
central
fires. It is probably owing to the escape of the elastic vapours
from
these spiracula that the modern earthquakes are of such small
extent
compared with those of remote antiquity, of which the vestiges
remain
all over the globe. 5. The great size and height of the continents,
and
the great size and depth of the South-sea, Atlantic, and other
oceans,
evince that the first earthquakes, which produced these immense
changes
in the globe, must have been occasioned by central fires. 6. The
very
distant and expeditious communication of the shocks of some great
earthquakes. The earthquake at Lisbon in 1755 was perceived in
Scotland,
in the Peak of Derbyshire, and in many other distant parts of
Europe.
The percussions of it travelled with about the velocity of sound,
viz.
about thirteen miles in a minute. The earthquake in 1693 extended
2600
leagues. (Goldsmith's History.) These phenomena are easily
explained if
the central parts of the earth consist of a fluid lava, as a
percussion
on one part of such a fluid mass would be felt on other parts of
its
confining vault, like a stroke on a fluid contained in a bladder,
which
however gentle on one side is perceptible to the hand placed on the
other; and the velocity with which such a concussion would travel
would
be that of sound, or thirteen miles in a minute. For further
information
on this part of the subject the reader is referred to Mr. Michell's
excellent Treatise on Earthquakes in the Philos. Trans. Vol. LI. 7.
That
there is a cavity at the center of the earth is made probable by
the
late experiments on the attraction of mountains by Mr. Maskerlyne,
who
supposed from other considerations that the density of the earth
near
the surface should be five times less than its mean density. Phil.
Trans. Vol. LXV. p. 498. But found from the attraction of the
mountain
Schehallien, that it is probable, the mean density of the earth is
but
double that of the hill. Ibid. p. 532. Hence if the first
supposition be
well founded there would appear to be a cavity at the centre of
considerable magnitude, from whence the immense beds and mountains
of
lava, toadstone, basaltes, granite, &c. have been protruded. 8. The
variation of the compass can only be accounted for by supposing the
central parts of the earth to consist of a fluid mass, and that
part of
this fluid is iron, which requiring a greater degree of heat to
bring it
into fusion than glass or other metals, remains a solid, and the
vis
inertiae of this fluid mass with the iron in it, occasions it to
perform
fewer revolutions than the crust of solid earth over it, and thus
it is
gradually left behind, and the place where the floating iron
resides is
pointed to by the direct or retrograde motions of the magnetic
needle.
This seems to have been nearly the opinion of Dr. Halley and Mr.
Euler.
Or sphere on sphere in widening waves expand,
And glad with genial warmth the incumbent land.
CANTO I. l. 143.
A certain quantity of heat seems to be combined with all bodies
besides
the sensible quantity which gravitates like the electric fluid
amongst
them. This combined heat or latent heat of Dr. Black, when set at
liberty by fermentation, inflammation, crystallization, freezing,
or
other chemical attractions producing new combinations,
passes as a
fluid element into the surrounding bodies. And by thawing,
diffusion of
neutral salts in water, melting, and other chemical solutions, a
portion of heat is attracted from the bodies in vicinity and enters
into
or becomes combined with the new solutions.
Hence a combination of metals with acids, of essential oils
and acids,
of alcohol and water, of acids and water, give out heat; whilst a
solution of snow in water or in acids, and of neutral salts
in water,
attract heat from the surrounding bodies. So the acid of nitre
mixed
with oil of cloves unites with it and produces a most violent
flame; the
same acid of nitre poured on snow instantly dissolves it and
produces
the greatest degree of cold yet known, by which at Petersburgh
quicksilver was first frozen in 1760.
Water may be cooled below 32 without being frozen, if it be placed
on a
solid floor and secured from agitation, but when thus cooled below
the
freezing point the least agitation turns part of it suddenly into
ice,
and when this sudden freezing takes place a thermometer placed in
it
instantly rises as some heat is given out in the act of
congelation, and
the ice is thus left with the same sensible degree of cold
as the
water had possessed before it was agitated, but is nevertheless now
combined with less latent heat.
A cubic inch of water thus cooled down to 32 deg. mixed with an
equal
quantity of boiling water at 212 deg. will cool it to the middle
number
between these two, or to 122. But a cubic inch of ice whose
sensible
cold also is but 32, mixed with an equal quantity of boiling water,
will
cool it six times as much as the cubic inch of cold water
above-mentioned, as the ice not only gains its share of the
sensible or
gravitating heat of the boiling water but attracts to itself also
and
combines with the quantity of latent heat which it had lost at the
time
of its congelation.
So boiling water will acquire but 212 deg. of heat under the common
pressure
of the atmosphere, but the steam raised from it by its expansion or
by
its solution in the atmosphere combines with and carries away a
prodigious quantity of heat which it again parts with on its
condensation; as is seen in common distillation where the large
quantity
of water in the worm-tub is so soon heated. Hence the evaporation
of
ether on a thermometer soon sinks the mercury below freezing, and
hence
a warmth of the air in winter frequently succeeds a shower.
When the matter of heat or calorique is set at liberty from its
combinations, as by inflammation, it passes into the surrounding
bodies,
which possess different capacities of acquiring their share of the
loose
or sensible heat; thus a pint measure of cold water at 48 deg.
mixed with a
pint of boiling water at 212 deg. will cool it to the degree
between these
two numbers, or to 154 deg., but it requires two pint measures of
quicksilver at 48 deg. of heat to cool one pint of water as above.
These and
other curious experiments are adduced by Dr. Black to evince the
existance of combined or latent heat in bodies, as has been
explained by
some of his pupils, and well illustrated by Dr. Crawford. The world
has
long been in expectation of an account of his discoveries on this
subject by the celebrated author himself.
As this doctrine of elementary heat in its fluid and combined state
is
not yet universally received, I shall here add two arguments in
support
of it drawn from different sources, viz. from the heat given out or
absorbed by the mechanical condensation or expansion of the air,
and
perhaps of other bodies, and from the analogy of the various
phenomena
of heat with those of electricity.
I. If a thermometer be placed in the receiver of an air-pump, and
the
air hastily exhausted, the thermometer will sink some degrees, and
the
glass become steamy; the same occurs in hastily admitting a part of
the
air again. This I suppose to be produced by the expansion of part
of the
air, both during the exhaustion and re-admission of it; and that
the air
so expanded becomes capable of attracting from the bodies in its
vicinity a part of their heat, hence the vapours contained in it
and the
glass receiver are for a time colder and the steam is precipitated.
That
the air thus parts with its moisture from the cold occasioned by
its
rarefaction and not simply by the rarefaction itself is evident,
because
in a minute or two the same rarefied air will again take up the dew
deposited on the receiver; and because water will evaporate sooner
in
rare than in dense air.
There is a curious phenomenon similar to this observed in the
fountain
of Hiero constructed on a large scale at the Chemnicensian mines in
Hungary. In this machine the air in a large vessel is compressed by
a
column of water 260 feet high, a stop-cock is then opened, and as
the
air issues out with great vehemence, and thus becomes immediately
greatly expanded, so much cold is produced that the moisture from
this
stream of air is precipitated in the form of snow, and ice is
formed
adhering to the nosel of the cock. This remarkable circumstance is
described at large with a plate of the machine in Philos. Trans.
Vol.
LII. for 1761.
The following experiment is related by Dr. Darwin in the Philos.
Trans.
Vol. LXXVIII. Having charged an air-gun as forcibly as he well
could the
air-cell and syringe became exceedingly hot, much more so than
could be
ascribed to the friction in working it; it was then left about half
an
hour to cool down to the temperature of the air, and a thermometer
having been previously fixed against a wall, the air was discharged
in a
continual stream on its bulb, and it sunk many degrees. From these
three
experiments of the steam in the exhausted receiver being deposited
and
re-absorbed, when a part of the air is exhausted or re-admitted,
and the
snow produced by the fountain of Hiero, and the extraordinary heat
given
out in charging, and the cold produced in discharging an air-gun,
there
is reason to conclude that when air is mechanically compressed the
elementary fluid heat is pressed out of it, and that when it is
mechanically expanded the same fluid heat is re-absorbed from the
common
mass.
It is probable all other bodies as well as air attract heat from
their
neighbours when they are mechanically expanded, and give it out
when
they are mechanically condensed. Thus when a vibration of the
particles
of hard bodies is excited by friction or by percussion, these
particles
mutually recede from and approach each other reciprocally; at the
times
of their recession from each other, the body becomes enlarged in
bulk,
and is then in a condition to attract heat from those in its
vicinity
with great and sudden power; at the times of their approach to each
other this heat is again given out, but the bodies in contact
having in
the mean while received the heat they had thus lost, from other
bodies
behind them, do not so suddenly or so forcibly re-absorb the heat
again
from the body in vibration; hence it remains on its surface like
the
electric fluid on a rubbed glass globe, and for the same reason,
because
there is no good conductor to take it up again. Hence at every
vibration
more and more heat is acquired and stands loose upon the surface;
as in
filing metals or rubbing glass tubes; and thus a smith with a few
strokes on a nail on his anvil can make it hot enough to light a
brimstone-match; and hence in striking flint and steel together
heat
enough is produced to vitrify the parts thus strucken off, the
quantity
of which heat is again probably increased by the new chemical
combination.
II. The analogy between the phenomena of the electric fluid and of
heat
furnishes another argument in support of the existence of heat as a
gravitating fluid. 1. They are both accumulated by friction on the
excited body. 2. They are propagated easily or with difficalty
along the
same classes of bodies; with ease by metals, with less ease by
water;
and with difficulty by resins, bees-wax, silk, air, and glass. Thus
glass canes or canes of sealing-wax may be melted by a blow-pipe or
a
candle within a quarter of an inch of the fingers which hold them,
without any inconvenient heat, while a pin or other metallic
substance
applyed to the flame of a candle so readily conducts the heat as
immediately to burn the fingers. Hence clothes of silk keep the
body
warmer than clothes of linen of equal thickness, by confining the
heat
upon the body. And hence plains are so much warmer than the summits
of
mountains by the greater density of the air confining the acquired
heat
upon them. 3. They both give out light in their passage through
air,
perhaps not in their passage through a vacuum. 4. They both of them
fuse
or vitrify metals. 5. Bodies after being electrized if they are
mechanically extended will receive a greater quantity of
electricity, as
in Dr. Franklin's experiment of the chain in the tankard; the same
seems
true in respect to heat as explained above. 6. Both heat and
electricity
contribute to suspend steam in the atmosphere by producing or
increasing
the repulsion of its particles. 7. They both gravitate, when they
have
been accumulated, till they find their equilibrium.
If we add to the above the many chemical experiments which receive
an
easy and elegant explanation from the supposed matter of heat, as
employed in the works of Bergman and Lavoisier, I think we may
reasonably allow of its existence as an element, occasionally
combined
with other bodies, and occasionally existing as a fluid, like the
electric fluid gravitating amongst them, and that hence it may be
propagated from the central fires of the earth to the whole mass,
and
contribute to preserve the mean heat of the earth, which in this
country
is about 48 degrees but variable from the greater or less effect of
the
sun's heat in different climates, so well explained in Mr. Kirwan's
Treatise on the Temperature of different Latitudes. 1787, Elmsly.
London.
So to the sacred Sun in Memnon's fane
Spontaneous concords quired the matin strain.
CANTO I. l. 183.
The gigantic statue of Memnon in his temple at Thebes had a lyre in
his
hands, which many credible writers assure us, sounded when the
rising
sun shone upon it. Some philosophers have supposed that the sun's
light
possesses a mechanical impulse, and that the sounds abovementioned
might
be thence produced. Mr. Michell constructed a very tender
horizontal
balance, as related by Dr. Priestley in his history of light and
colours, for this purpose, but some experiments with this balance
which
I saw made by the late Dr. Powel, who threw the focus of a large
reflector on one extremity of it, were not conclusive either way,
as the
copper leaf of the balance approached in one experiment and receded
in
another.
There are however methods by which either a rotative or alternating
motion may be produced by very moderate degrees of heat. If a
straight
glass tube, such as are used for barometers, be suspended
horizontally
before a fire, like a roasting spit, it will revolve by intervals;
for
as glass is a bad conductor of heat the side next the fire becomes
heated sooner than the opposite side, and the tube becomes bent
into a
bow with the external part of the curve towards the fire, this
curve
then falls down and produces a fourth part of a revolution of the
glass
tube, which thus revolves with intermediate pauses.
Another alternating motion I have seen produced by suspending a
glass
tube about eight inches long with bulbs at each end on a centre
like a
scale beam. This curious machine is filled about one third part
with
purest spirit of wine, the other two thirds being a vacuum, and is
called a pulse-glass, if it be placed in a box before the fire, so
that
either bulb, as it rises, may become shaded from the fire, and
exposed
to it when it descends, an alternate libration of it is produced.
For
spirit of wine in vacuo emits steam by a very small degree of heat,
and
this steam forces the spirit beneath it up into the upper bulb,
which
therefore descends. It is probable such a machine on a larger scale
might be of use to open the doors or windows of hot-houses or
mellon-
frames, when the air within them should become too much heated, or
might
be employed in more important mechanical purposes.
On travelling through a hot summer's day in a chaise with a box
covered
with leather on the fore-axle-tree, I observed, as the sun shone
upon
the black leather, the box began to open its lid, which at noon
rose
above a foot, and could not without great force be pressed down;
and
which gradually closed again as the sun declined in the evening.
This I
suppose might with still greater facility be applied to the purpose
of
opening melon-frames or the sashes of hot-houses.
The statue of Memnon was overthrown and sawed in two by Cambyses to
discover its internal structure, and is said still to exist. See
Savary's Letters on Egypt. The truncated statue is said for many
centuries to have saluted the rising sun with chearful tones, and
the
setting sun with melancholy ones.
Star of the earth, and diamond of the night.
CANTO I. l. 196.
There are eighteen species of Lampyris or glow-worm, according to
Linneus, some of which are found in almost every part of the world.
In
many of the species the females have no wings, and are supposed to
be
discovered by the winged males by their shining in the night. They
become much more lucid when they put themselves in motion, which
would
seem to indicate that their light is owing to their respiration; in
which process it is probable phosphoric acid is produced by the
combination of vital air with some part of the blood, and that
light is
given out through their transparent bodies by this slow internal
combustion.
There is a fire-fly of the beetle-kind described in the Dict.
Raisonne
under the name of Acudia, which is said to be two inches long, and
inhabits the West-Indies and South America; the natives use them
instead
of candles, putting from one to three of them under a glass. Madam
Merian says, that at Surinam the light of this fly is so great,
that she
saw sufficiently well by one of them to paint and finish one of the
figures of them in her work on insects. The largest and oldest of
them
are said to become four inches long, and to shine like a shooting
star
as they fly, and are thence called Lantern-bearers. The use of this
light to the insect itself seems to be that it may not fly against
objects in the night; by which contrivance these insects are
enabled to
procure their sustenance either by night or day, as their wants may
require, or their numerous enemies permit them; whereas some of our
beetles have eyes adapted only to the night, and if they happen to
come
abroad too soon in the evening are so dazzled that they fly against
every thing in their way. See note on Phosphorus, No. X.
In some seas, as particularly about the coast of Malabar, as a ship
floats along, it seems during the night to be surrounded with fire,
and
to leave a long tract of light behind it. Whenever the sea is
gently
agitated it seems converted into little stars, every drop as it
breaks
emits light, like bodies electrified in the dark. Mr. Bomare says,
that
when he was at the port of Cettes in Languedoc, and bathing with a
companion in the sea after a very hot day, they both appeared
covered
with fire after every immersion, and that laying his wet hand on
the arm
of his companion, who had not then dipped himself, the exact mark
of his
hand and fingers was seen in characters of fire. As numerous
microscopic
insects are found in this shining water, its light has been
generally
ascribed to them, though it seems probable that fish-slime in hot
countries may become in such a state of incipient putrefaction as
to
give light, especially when by agitation it is more exposed to the
air;
otherwise it is not easy to explain why agitation should be
necessary to
produce this marine light. See note on Phosphorus No. X.
Or mark in shining letters Kunckel's name
In the pale phosphor's self-consuming flame.
CANTO I. l. 231.
Kunckel, a native of Hamburgh, was the first who discovered to the
world
the process for producing phosphorus; though Brandt and Boyle were
likewise said to have previously had the art of making it. It was
obtained from sal microcosmicum by evaporation in the form of an
acid,
but has since been found in other animal substances, as in the
ashes of
bones, and even in some vegetables, as in wheat flour. Keir's
chemical
Dict. This phosphoric acid is like all other acids united with
vital
air, and requires to be treated with charcoal or phlogiston to
deprive
it of this air, it then becomes a kind of animal sulphur, but of so
inflammable a nature, that on the access of air it takes fire
spontaneously, and as it burns becomes again united with vital air,
and
re-assumes its form of phosphoric acid.
As animal respiration seems to be a kind of slow combustion, in
which it
is probable that phosphoric acid is produced by the union of
phosphorus
with the vital air, so it is also probable that phosphoric acid is
produced in the excretory or respiratory vessels of luminous
insects, as
the glow-worm and fire-fly, and some marine insects. From the same
principle I suppose the light from putrid fish, as from the heads
of
hadocks, and from putrid veal, and from rotten wood in a certain
state
of their putrefaction, is produced, and phosphorus thus slowly
combined
with air is changed into phosphoric acid. The light from the
Bolognian
stone, and from calcined shells, and from white paper, and linen
after
having been exposed for a time to the sun's light, seem to produce
either the phosphoric or some other kind of acid from the
sulphurous or
phlogistic matter which they contain. See note on Beccari's shells.
l.
180.
There is another process seems similar to this slow combustion, and
that
is bleaching. By the warmth and light of the sun the water
sprinkled
upon linen or cotton cloth seems to be decomposed, (if we credit
the
theory of M. Lavoisier,) and a part of the vital air thus set at
liberty
and uncombined and not being in its elastic form, more easily
dissolves
the colouring or phlogistic matter of the cloth, and produces a new
acid, which is itself colourless, or is washed out of the cloth by
water. The new process of bleaching confirms a part of this theory,
for
by uniting much vital air to marine acid by distilling it from
manganese, on dipping the cloth to be bleached in water repleat
with
this super-aerated marine acid, the colouring matter disappears
immediately, sooner indeed in cotton than in linen. See note XXXIV.
There is another process which I suspect bears analogy to these
above-
mentioned, and that is the rancidity of animal fat, as of bacon; if
bacon be hung up in a warm kitchen, with much salt adhering on the
outside of it, the fat part of it soon becomes yellow and rancid;
if it
be washed with much cold water after it has imbibed the salt, and
just
before it is hung up, I am well informed, that it will not become
rancid, or in very slight degrees. In the former case I imagine the
salt
on the surface of the bacon attracts water during the cold of the
night,
which is evaporated during the day, and that in this evaporation a
part
of the water becomes decomposed, as in bleaching, and its vital air
uniting with greater facility in its unelastic state with the
animal
fat, produces an acid, perhaps of the phosphoric kind, which being
of a
fixed nature lies upon the bacon, giving it the yellow colour and
rancid
taste. It is remarkable that the super-aerated marine acid does not
bleach living animal substances, at least it did not whiten a part
of my
hand which I for some minutes exposed to it.
Quick moves the balanced beam, of giant-birth,
Wields his large limbs, and nodding shakes the earth.
CANTO I. l. 261.
The expansive force of steam was known in some degree to the
antients,
Hero of Alexandria describes an application of it to produce a
rotative
motion by the re-action of steam issuing from a sphere mounted upon
an
axis, through two small tubes bent into tangents, and issuing from
the
opposite sides of the equatorial diameter of the sphere, the sphere
was
supplied with steam by a pipe communicating with a pan of boiling
water,
and entering the sphere at one of its poles.
A french writer about the year 1630 describes a method of raising
water
to the upper part of a house by filling a chamber with steam, and
suffering it to condense of itself, but it seems to have been mere
theory, as his method was scarcely practicable as he describes it.
In
1655 the Marquis of Worcester mentions a method of raising water by
fire
in his Century of Inventions, but he seems only to have availed
himself
of the expansive force and not to have known the advantages arising
from
condensing the steam by an injection of cold water. This latter and
most
important improvement seems to have been made by Capt. Savery
sometime
prior to 1698, for in that year his patent for the use of that
invention
was confirmed by act of parliament. This gentleman appears to have
been
the first who reduced the machine to practice and exhibited it in
an
useful form. This method consisted only in expelling the air from a
vessel by steam and condensing the steam by an injection of cold
water,
which making a vacuum, the pressure of the atmosphere forced the
water
to ascend into the steam-vessel through a pipe of 24 to 26 feet
high,
and by the admission of dense steam from the boiler, forcing the
water
in the steam-vessel to ascend to the height desired. This
construction
was defective because it required very strong vessels to resist the
force of the steam, and because an enormous quantity of steam was
condensed by coming in contact with the cold water in the
steam-vessel.
About or soon after that time M. Papin attempted a steam-engine on
similar principles but rather more defective in its construction.
The next improvement was made very soon afterwards by Messrs.
Newcomen
and Cawley of Dartmouth, it consisted in employing for the
steam-vessel
a hollow cylinder, shut at bottom and open at top, furnished with a
piston sliding easily up and down in it, and made tight by oakum or
hemp, and covered with water. This piston is suspended by chains
from
one end of a beam, moveable upon an axis in the middle of its
length, to
the other end of this beam are suspended the pump-rods.
The danger of bursting the vessels was avoided in this machine, as
however high the water was to be raised it was not necessary to
increase
the density of the steam but only to enlarge the diameter of the
cylinder.
Another advantage was, that the cylinder not being made so cold as
in
Savary's method, much less steam was lost in filling it after each
condensation.
The machine however still remained imperfect, for the cold water
thrown
into the cylinder acquired heat from the steam it condensed, and
being
in a vessel exhausted of air it produced steam itself, which in
part
resisted the action of the atmosphere on the piston; were this
remedied
by throwing in more cold water the destruction of steam in the next
filling of the cylinder would be proportionally increased. It has
therefore in practice been found adviseable not to load these
engines
with columns of water weighing more than seven pounds for each
square
inch of the area of the piston. The bulk of water when converted
into
steam remained unknown until Mr. J. Watt, then of Glasgow, in 1764,
determined it to be about 1800 times more rare than water. It soon
occurred to Mr. Watt that a perfect engine would be that in which
no
steam should be condensed in filling the cylinder, and in which the
steam should be so perfectly cooled as to produce nearly a perfect
vacuum.
Mr. Watt having ascertained the degree of heat in which water
boiled in
vacuo, and under progressive degrees of pressure, and instructed by
Dr.
Black's discovery of latent heat, having calculated the quantity of
cold
water necessary to condense certain quantities of steam so far as
to
produce the exhaustion required, he made a communication from the
cylinder to a cold vessel previously exhausted of air and water,
into
which the steam rushed by its elasticity, and became immediately
condensed. He then adapted a cover to the cylinder and admitted
steam
above the piston to press it down instead of air, and instead of
applying water he used oil or grease to fill the pores of the oakum
and
to lubricate the cylinder.
He next applied a pump to extract the injection water, the
condensed
steam, and the air, from the condensing vessel, every stroke of the
engine.
To prevent the cooling of the cylinder by the contact of the
external
air, he surrounded it with a case containing steam, which he again
protected by a covering of matters which conduct heat slowly.
This construction presented an easy means of regulating the power
of the
engine, for the steam being the acting power, as the pipe which
admits
it from the boiler is more or less opened, a greater or smaller
quantity
can enter during the time of a stroke, and consequently the engine
can
act with exactly the necessary degree of energy.
Mr. Watt gained a patent for his engine in 1768, but the further
persecution of his designs were delayed by other avocations till
1775,
when in conjunction with Mr. Boulton of Soho near Birmingham,
numerous
experiments were made on a large scale by their united ingenuity,
and
great improvements added to the machinery, and an act of parliament
obtained for the prolongation of their patent for twenty-five
years,
they have since that time drained many of the deep mines in
Cornwall,
which but for the happy union of such genius must immediately have
ceased to work. One of these engines works a pump of eighteen
inches
diameter, and upwards of 100 fathom or 600 feet high, at the rate
of ten
to twelve strokes of seven feet long each, in a minute, and that
with
one fifth part of the coals which a common engine would have taken
to do
the same work. The power of this engine may be easier comprehended
by
saying that it raised a weight equal to 81000 pounds 80 feet high
in a
minute, which is equal to the combined action of 200 good horses.
In
Newcomen's engine this would have required a cylinder of the
enormous
diameter of 120 inches or ten feet, but as in this engine of Mr.
Watt
and Mr. Boulton the steam acts, and a vacuum is made, alternately
above
and below the piston, the power exerted is double to what the same
cylinder would otherways produce, and is further augmented by an
inequality in the length of the two ends of the lever.
These gentlemen have also by other contrivances applied their
engines to
the turning of mills for almost every purpose, of which that great
pile
of machinery the Albion Mill is a well known instance. Forges,
slitting
mills, and other great works are erected where nature has furnished
no
running water, and future times may boast that this grand and
useful
engine was invented and perfected in our own country.
Since the above article went to the press the Albion Mill is no
more; it
is supposed to have been set on fire by interested or malicious
incendaries, and is burnt to the ground. Whence London has lost the
credit and the advantage of possessing the most powerful machine in
the
world!
In phalanx firm the fiend of Frost assail.
CANTO I. l. 439.
The cause of the expansion of water during its conversion into ice
is
not yet well ascertained, it was supposed to have been owing to the
air
being set at liberty in the act of congelation which was before
dissolved in the water, and the many air bubbles in ice were
thought to
countenance this opinion. But the great force with which ice
expands
during its congelation, so as to burst iron bombs and coehorns,
according to the experiments of Major Williams at Quebec,
invalidates
this idea of the cause of it, and may sometime be brought into use
as a
means of breaking rocks in mining, or projecting cannon-balls, or
for
other mechanical purposes, if the means of producing congelation
should
ever be discovered to be as easy as the means of producing
combustion.
Mr. de Mairan attributes the increase of bulk of frozen water to
the
different arrangement of the particles of it in crystallization, as
they
are constantly joined at an angle of 60 degrees; and must by this
disposition he thinks occupy a greater volume than if they were
parallel. He found the augmentation of the water during freezing to
amount to one-fourteenth, one-eighteenth, one-nineteenth, and when
the
water was previously purged of air to only one-twenty-second part.
He
adds that a piece of ice, which was at first only one-fourteenth
part
specifically lighter than water, on being exposed some days to the
frost
became one-twelfth lighter than water. Hence he thinks ice by being
exposed to greater cold still increases in volume, and to this
attributes the bursting of ice in ponds and on the glaciers. See
Lewis's
Commerce of Arts, p. 257. and the note on Muschus in the other
volume of
this work.
This expansion of ice well accounts for the greater mischief done
by
vernal frosts attended with moisture, (as by hoar-frosts,) than by
the
dry frosts called black frosts. Mr. Lawrence in a letter to Mr.
Bradley
complains that the dale-mist attended with a frost on may-day had
destroyed all his tender fruits; though there was a sharper frost
the
night before without a mist, that did him no injury; and adds, that
a
garden not a stone's throw from his own on a higher situation,
being
above the dale-mist, had received no damage. Bradley, Vol. II. p.
232.
Mr. Hunter by very curious experiments discovered that the living
principle in fish, in vegetables, and even in eggs and seeds,
possesses
a power of resisting congelation. Phil. Trans. There can be no
doubt but
that the exertions of animals to avoid the pain of cold may produce
in
them a greater quantity of heat, at least for a time, but that
vegetables, eggs, or seeds, should possess such a quality is truly
wonderful. Others have imagined that animals possess a power of
preventing themselves from becoming much warmer than 98 degrees of
heat,
when immersed in an atmosphere above that degree of heat. It is
true
that the increased exhalation from their bodies will in some
measure
cool them, as much heat is carried off by the evaporation of
fluids, but
this is a chemical not an animal process. The experiments made by
those
who continued many minutes in the air of a room heated so much
above any
natural atmospheric heat, do not seem conclusive, as they remained
in it
a less time than would have been necessary to have heated a mass of
beef
of the same magnitude, and the circulation of the blood in living
animals, by perpetually bringing new supplies of fluid to the skin,
would prevent the external surface from becoming hot much sooner
than
the whole mass. And thirdly, there appears no power of animal
bodies to
produce cold in diseases, as in scarlet fever, in which the
increased
action of the vessels of the skin produces heat and contributes to
exhaust the animal power already too much weakened.
It has been thought by many that frosts meliorate the ground, and
that
they are in general salubrious to mankind. In respect to the former
it
is now well known that ice or snow contain no nitrous particles,
and
though frost by enlarging the bulk of moist clay leaves it softer
for a
time after the thaw, yet as soon as the water exhales, the clay
becomes
as hard as before, being pressed together by the incumbent
atmosphere,
and by its self-attraction, called setting by the potters.
Add to this
that on the coasts of Africa, where frost is unknown, the fertility
of
the soil is almost beyond our conceptions of it. In respect to the
general salubrity of frosty seasons the bills of mortality are an
evidence in the negative, as in long frosts many weakly and old
people
perish from debility occasioned by the cold, and many classes of
birds
and other wild animals are benumbed by the cold or destroyed by the
consequent scarcity of food, and many tender vegetables perish from
the
degree of cold.
I do not think it should be objected to this doctrine that there
are
moist days attended with a brisk cold wind when no visible ice
appears,
and which are yet more disagreeable and destructive than frosty
weather.
For on these days the cold moisture, which is deposited on the skin
is
there evaporated and thus produces a degree of cold perhaps greater
than
the milder frosts. Whence even in such days both the disagreeable
sensations and insalubrious effects belong to the cause
abovementioned,
viz. the intensity of the cold. Add to this that in these cold
moist
days as we pass along or as the wind blows upon us, a new sheet of
cold
water is as it were perpetually applied to us and hangs upon our
bodies,
now as water is 800 times denser than air and is a much better
conductor
of heat, we are starved with cold like those who go into a cold
bath,
both by the great number of particles in contact with the skin and
their
greater facility of receiving our heat.
It may nevertheless be true that snows of long duration in our
winters
may be less injurious to vegetation than great rains and shorter
frosts,
for two reasons. 1. Because great rains carry down many thousand
pounds
worth of the best part of the manure off the lands into the sea,
whereas
snow dissolves more gradually and thence carries away less from the
land; any one may distinguish a snow-flood from a rain-flood by the
transparency of the water. Hence hills or fields with considerable
inclination of surface should be ploughed horizontally that the
furrows
may stay the water from showers till it deposits its mud. 2. Snow
protects vegetables from the severity of the frost, since it is
always
in a state of thaw where it is in contact with the earth; as the
earth's
heat is about 48 deg. and the heat of thawing snow is 32 deg. the
vegetables
between them are kept in a degree of heat about 40, by which many
of
them are preserved. See note on Muschus, Vol. II. of this work.
Cold from each point cerulean lustres gleam.
CANTO I. l. 339.
ELECTRIC POINTS.
There was an idle dispute whether knobs or points were preferable
on the
top of conductors for the defence of houses. The design of these
conductors is to permit the electric matter accumulated in the
clouds to
pass through them into the earth in a smaller continued stream as
the
cloud approaches, before it comes to what is termed striking
distance;
now as it is well known that accumulated electricity will pass to
points
at a much greater distance than it will to knobs there can be no
doubt
of their preference; and it would seem that the finer the point and
the
less liable to become rusty the better, as it would take off the
lightening while it was still at a greater distance, and by that
means
preserve a greater extent of building; the very extremity of the
point
should be of pure silver or gold, and might be branched into a kind
of
brush, since one small point can not be supposed to receive so
great a
quantity as a thicker bar might conduct into the earth.
If an insulated metallic ball is armed with a point, like a needle,
projecting from one part of it, the electric fluid will be seen in
the
dark to pass off from this point, so long as the ball is kept
supplied
with electricity. The reason of this is not difficult to
comprehend,
every part of the electric atmosphere which surrounds the insulated
ball
is attracted to that ball by a large surface of it, whereas the
electric
atmosphere which is near the extremity of the needle is attracted
to it
by only a single point, in consequence the particles of electric
matter
near the surface of the ball approach towards it and push off by
their
greater gravitation the particles of electric matter over the point
of
the needle in a continued stream.
Something like this happens in respect to the diffusion of oil on
water
from a pointed cork, an experiment which was many years ago shewn
me by
Dr. Franklin; he cut a piece of cork about the size of a
letter-wafer
and left on one edge of it a point about a sixth of an inch in
length
projecting as a tangent to the circumference. This was dipped in
oil and
thrown on a pond of water and continued to revolve as the oil left
the
point for a great many minutes. The oil descends from the floating
cork
upon the water being diffused upon it without friction and perhaps
without contact; but its going off at the point so forcibly as to
make
the cork revolve in a contrary direction seems analogous to the
departure of the electric fluid from points.
Can any thing similar to either of these happen in respect to the
earth's atmosphere and give occasion to the breezes on the tops of
mountains, which may be considered as points on the earths
circumference?
FAIRY-RINGS.
There is a phenomenon supposed to be electric which is yet
unaccounted
for, I mean the Fairy-rings, as they are called, so often seen on
the
grass. The numerous flashes of lightning which occur every summer
are, I
believe, generally discharged on the earth, and but seldom (if
ever)
from one cloud to another. Moist trees are the most frequent
conductors
of these flashes of lightning, and I am informed by purchasers of
wood
that innumerable trees are thus cracked and injured. At other times
larger parts or prominences of clouds gradually sinking as they
move
along, are discharged on the moisture parts of grassy plains. Now
this
knob or corner of a cloud in being attracted by the earth will
become
nearly cylindrical, as loose wool would do when drawn out into a
thread,
and will strike the earth with a stream of electricity perhaps two
or
ten yards in diameter. Now as a stream of electricity displaces the
air
it passes through, it is plain no part of the grass can be burnt by
it,
but just the external ring of this cylinder where the grass can
have
access to the air, since without air nothing can be calcined. This
earth
after having been so calcined becomes a richer soil, and either
funguses
or a bluer grass for many years mark the place. That lightning
displaces
the air in its passage is evinced by the loud crack that succeeds
it,
which is owing to the sides of the aerial vacuum clapping together
when
the lightning is withdrawn. That nothing will calcine without air
is now
well understood from the acids produced in the burning of
phlogistic
substances, and may be agreeably seen by suspending a paper on an
iron
prong and putting it into the centre of the blaze of an
iron-furnace; it
may be held there some seconds and may be again withdrawn without
its
being burnt, if it be passed quickly into the flame and out again
through the external part of it which is in contact with the air. I
know
some circles of many yards diameter of this kind near Foremark in
Derbyshire which annually produce large white funguses and stronger
grass, and have done so, I am informed, above thirty years. This
increased fertility of the ground by calcination or charring, and
its
continuing to operate so many years is well worth the attention of
the
farmer, and shews the use of paring and burning new turf in
agriculture,
which produces its effect not so much by the ashes of the vegetable
fibres as by charring the soil which adheres to them.
These situations, whether from eminence or from moisture, which
were
proper once to attract and discharge a thunder-cloud, are more
liable
again to experience the same. Hence many fairy-rings are often seen
near
each other either without intersecting each other, as I saw this
summer
in a garden in Nottinghamshire, or intersecting each other as
described
on Arthur's seat near Edinburgh in the Edinb. Trans. Vol. II. p. 3.
Where dwell my vegetative realms benumb'd
In buds imprison'd, or in bulbs intomb'd.
CANTO I. l. 459.
A tree is properly speaking a family or swarm of buds, each bud
being an
individual plant, for if one of these buds be torn or cut out and
planted in the earth with a glass cup inverted over it to prevent
its
exhalation from being at first greater than its power of
absorption, it
will produce a tree similar to its parent; each bud has a leaf,
which is
its lungs, appropriated to it, and the bark of the tree is a
congeries
of the roots of these individual buds, whence old hollow trees are
often
seen to have some branches flourish with vigour after the internal
wood
is almost intirely decayed and vanished. According to this idea
Linneus
has observed that trees and shrubs are roots above ground, for if a
tree
be inverted leaves will grow from the root-part and roots from the
trunk-part. Phil. Bot p. 39. Hence it appears that vegetables have
two
methods of propagating themselves, the oviparous as by seeds, and
the
viviparous as by their buds and bulbs, and that the individual
plants,
whether from seeds or buds or bulbs, are all annual productions
like
many kinds of insects as the silk-worm, the parent perishing in the
autumn after having produced an embryon, which lies in a torpid
state
during the winter, and is matured in the succeeding summer. Hence
Linneus names buds and bulbs the winter-cradles of the plant or
hybernacula, and might have given the same term to seeds. In warm
climates few plants produce buds, as the vegetable life can be
compleated in one summer, and hence the hybernacle is not wanted;
in
cold climates also some plants do not produce buds, as
philadelphus,
frangula, viburnum, ivy, heath, wood-nightshade, rue, geranium.
The bulbs of plants are another kind of winter-cradle, or
hybernacle,
adhering to the descending trunk, and are found in the perennial
herbaceous plants which are too tender to bear the cold of the
winter.
The production of these subterraneous winter lodges, is not yet
perhaps
clearly understood, they have been distributed by Linneus according
to
their forms into scaly, solid, coated, and jointed bulbs, which
however
does not elucidate their manner of production. As the buds of trees
may
be truly esteemed individual annual plants, their roots
constituting the
bark of the tree, it follows that these roots (viz. of each
individual
bud) spread themselves over the last years bark, making a new bark
over
the old one, and thence descending cover with a new bark the old
roots
also in the same manner. A similar circumstance I suppose to happen
in
some herbaceous plants, that is, a new bark is annually produced
over
the old root, and thus for some years at least the old root or
caudex
increases in size and puts up new stems. As these roots increase in
size
the central part I suppose changes like the internal wood of a tree
and
does not possess any vegetable life, and therefore gives out no
fibres
or rootlets, and hence appears bitten off, as in valerian,
plantain, and
devil's-bit. And this decay of the central part of the root I
suppose
has given occasion to the belief of the root-fibres drawing down
the
bulb so much insisted on by Mr. Milne in his Botanical Dictionary,
Art.
Bulb.
From the observations and drawings of various kinds of bulbous
roots at
different times of their growth, sent me by a young lady of nice
observation, it appears probable that all bulbous roots properly so
called perish annually in this climate: Bradley, Miller, and the
Author
of Spectacle de la Nature, observe that the tulip annually renews
its
bulb, for the stalk of the old flower is found under the old dry
coat
but on the outside of the new bulb. This large new bulb is the
flowering
bulb, but besides this there are other small new bulbs produced
between
the coats of this large one but from the same caudex, (or circle
from
which the root-fibres spring;) these small bulbs are leaf-bearing
bulbs,
and renew themselves annually with increasing size till they bear
flowers.
Miss ——favoured me with the following curious experiment: She
took a
small tulip-root out of the earth when the green leaves were
sufficiently high to show the flower, and placed it in a glass of
water;
the leaves and flower soon withered and the bulb became wrinkled
and
soft, but put out one small side bulb and three bulbs beneath
descending
an inch into the water by long processes from the caudex, the old
bulb
in some weeks intirely decayed; on dissecting this monster, the
middle
descending bulb was found by its process to adhere to the caudex
and to
the old flower-stem, and the side ones were separated from the
flower-
stem by a few shrivelled coats but adhered to the caudex. Whence
she
concludes that these last were off-sets or leaf-bulbs which should
have
been seen between the coats of the new flower-bulb if it had been
left
to grow in the earth, and that the middle one would have been the
new
flower-bulb. In some years (perhaps in wet seasons) the florists
are
said to lose many of their tulip-roots by a similar process, the
new
leaf-bulbs being produced beneath the old ones by an elongation of
the
caudex without any new flower-bulbs.
By repeated dissections she observes that the leaf-bulbs or
off-sets of
tulip, crocus, gladiolus, fritillary, are renewed in the same
manner as
the flowering-bulbs, contrary to the opinion of many writers; this
new
leaf-bulb is formed on the inside of the coats from whence the
leaves
grow, and is more or less advanced in size as the outer coats and
leaves
are more or less shrivelled. In examining tulip, iris, hyacinth,
hare-
bell, the new bulb was invariably found between the
flower-stem and
the base of the innermost leaf of those roots which had flowered,
and
inclosed by the base of the innermost leaf in those roots
which had
not flowered, in both cases adhering to the caudex or fleshy circle
from
which the root-fibres spring.
Hence it is probable that the bulbs of hyacinths are renewed
annually,
but that this is performed from the caudex within the old bulb, the
outer coat of which does not so shrivel as in crocus and fritillary
and
hence this change is not so apparent. But I believe as soon as the
flower is advanced the new bulbs may be seen on dissection, nor
does the
annual increase of the size of the root of cyclamen and of aletris
capensis militate against this annual renewal of them, since the
leaf-
bulbs or off-sets, as described above, are increased in size as
they are
annually renewed. See note on orchis, and on anthoxanthum, in Vol.
II.
of this work.
From the deep craters of his realms of fire
The whirling sun this ponderous planet hurld.
CANTO II. l. 14.
Dr. Alexander Wilson, Professor of Astronomy at Glasgow, published
a
paper in the Philosophical Transactions for 1774, demonstrating
that the
spots in the sun's disk are real cavities, excavations through the
luminous material, which covers the other parts of the sun's
surface.
One of these cavities he found to be about 4000 miles deep and many
times as wide. Some objections were made to this doctrine by M. De
la
Laude in the Memoirs of the French Academy for the year 1776, which
however have been ably answered by Professor Wilson in reply in the
Philos. Trans. for 1783. Keil observes, in his Astronomical
Lectures, p.
44, “We frequently see spots in the sun which are larger and
broader not
only than Europe or Africa, but which even equal, if they do not
exceed,
the surface of the whole terraqueous globe.” Now that these
cavities are
made in the sun's body by a process of nature similar to our
earthquakes
does not seem improbable on several accounts. 1. Because from this
discovery of Dr. Wilson it appears that the internal parts of the
sun
are not in a state of inflammation or of ejecting light, like the
external part or luminous ocean which covers it; and hence that a
greater degree of heat or inflammation and consequent expansion or
explosion may occasionally be produced in its internal or dark
nucleus.
2. Because the solar spots or cavities are frequently increased or
diminished in size. 3. New ones are often produced. 4. And old ones
vanish. 5. Because there are brighter or more luminous parts of the
sun's disk, called faculae by Scheiner and Hevelius, which would
seem to
be volcanos in the sun, or, as Dr. Wilson calls them, “eructations
of
matter more luminous than that which covers the sun's surface.” 6.
To
which may be added that all the planets added together with their
satellites do not amount to more than one six hundred and fiftieth
part
of the mass of the sun according to Sir Isaac Newton.
Now if it could be supposed that the planets were originally thrown
out
of the sun by larger sun-quakes than those frequent ones which
occasion
these spots or excavations above-mentioned, what would happen? 1.
According to the observations and opinion of Mr. Herschel the sun
itself
and all its planets are moving forwards round some other centre
with an
unknown velocity, which may be of opake matter corresponding with
the
very antient and general idea of a chaos. Whence if a ponderous
planet,
as Saturn, could be supposed to be projected from the sun by an
explosion, the motion of the sun itself might be at the same time
disturbed in such a manner as to prevent the planet from falling
again
into it. 2. As the sun revolves round its own axis its form must be
that
of an oblate spheroid like the earth, and therefore a body
projected
from its surface perpendicularly upwards from that surface would
not
rise perpendicularly from the sun's centre, unless it happened to
be
projected exactly from either of its poles or from its equator.
Whence
it may not be necessary that a planet if thus projected from the
sun by
explosion should again fall into the sun. 3. They would part from
the
sun's surface with the velocity with which that surface was moving,
and
with the velocity acquired by the explosion, and would therefore
move
round the sun in the same direction in which the sun rotates on its
axis, and perform eliptic orbits. 4. All the planets would move the
same
way round the sun, from this first motion acquired at leaving its
surface, but their orbits would be inclined to each other according
to
the distance of the part, where they were thrown out, from the
sun's
equator. Hence those which were ejected near the sun's equator
would
have orbits but little inclined to each other, as the primary
planets;
the plain of all whose orbits are inclined but seven degrees and a
half
from each other. Others which were ejected near the sun's poles
would
have much more eccentric orbits, as they would partake so much less
of
the sun's rotatory motion at the time they parted from his surface,
and
would therefore be carried further from the sun by the velocity
they had
gained by the explosion which ejected them, and become comets. 5.
They
would all obey the same laws of motion in their revolutions round
the
sun; this has been determined by astronomers, who have demonstrated
that
they move through equal areas in equal times. 6. As their annual
periods
would depend on the height they rose by the explosion, these would
differ in them all. 7. As their diurnal revolutions would depend on
one
side of the exploded matter adhering more than the other at the
time it
was torn off by the explosion, these would also differ in the
different
planets, and not bear any proportion to their annual periods. Now
as all
these circumstances coincide with the known laws of the planetary
system, they serve to strengthen this conjecture.
This coincidence of such a variety of circumstances induced M. de
Buffon
to suppose that the planets were all struck off from the sun's
surface
by the impact of a large comet, such as approached so near the
sun's
disk, and with such amazing velocity, in the year 1680, and is
expected
to return in 2255. But Mr. Buffon did not recollect that these
comets
themselves are only planets with more eccentric orbits, and that
therefore it must be asked, what had previously struck off these
comets
from the sun's body? 2. That if all these planets were struck off
from
the sun at the same time, they must have been so near as to have
attracted each other and have formed one mass: 3. That we shall
want new
causes for separating the secondary planets from the primary ones,
and
must therefore look out for some other agent, as it does not appear
how
the impulse of a comet could have made one planet roll round
another at
the time they both of them were driven off from the surface of the
sun.
If it should be asked, why new planets are not frequently ejected
from
the sun? it may be answered, that after many large earthquakes many
vents are left for the elastic vapours to escape, and hence, by the
present appearance of the surface of our earth, earthquakes
prodigiously
larger than any recorded in history have existed; the same
circumstances
may have affected the sun, on whose surface there are appearances
of
volcanos, as described above. Add to this, that some of the comets,
and
even the georgium sidus, may, for ought we know to the contrary,
have
been emitted from the sun in more modern days, and have been
diverted
from their course, and thus prevented from returning into the sun,
by
their approach to some of the older planets, which is somewhat
countenanced by the opinion several philosophers have maintained,
that
the quantity of matter of the sun has decreased. Dr. Halley
observed,
that by comparing the proportion which the periodical time of the
moon
bore to that of the sun in former times, with the proportion
between
them at present, that the moon is found to be somewhat accelerated
in
respect to the sun. Pemberton's View of Sir Isaac Newton, p. 247.
And so
large is the body of this mighty luminary, that all the planets
thus
thrown out of it would make scarcely any perceptible diminution of
it,
as mentioned above. The cavity mentioned above, as measured by Dr.
Wilson of 4000 miles in depth, not penetrating an hundredth part of
the
sun's semi-diameter; and yet, as its width was many times greater
than
its depth, was large enough to contain a greater body than our
terrestrial world.
I do not mean to conceal, that from the laws of gravity unfolded by
Sir
Isaac Newton, supposing the sun to be a sphere and to have no
progressive motion, and not liable itself to be disturbed by the
supposed projection of the planets from it, that such planets must
return into the sun. The late Rev. William Ludlam, of Leicester,
whose
genius never met with reward equal to its merits, in a letter to
me,
dated January, 1787, after having shewn, as mentioned above, that
planets so projected from the sun would return to it, adds, “That a
body
as large as the moon so projected, would disturb the motion of the
earth
in its orbit, is certain; but the calculation of such disturbing
forces
is difficult. The body in some circumstances might become a
satellite,
and both move round their common centre of gravity, and that centre
be
carried in an annual orbit round the sun.”
There are other circumstances which might have concurred at the
time of
such supposed explosions, which would render this idea not
impossible.
1. The planets might be thrown out of the sun at the time the sun
itself
was rising from chaos, and be attracted by other suns in their
vicinity
rising at the same time out of chaos, which would prevent them from
returning into the sun. 2. The new planet in its course or ascent
from
the sun, might explode and eject a satellite, or perhaps more than
one,
and thus by its course being affected might not return into the
sun. 3.
If more planets were ejected at the same time from the sun, they
might
attract and disturb each others course at the time they left the
body of
the sun, or very soon afterwards, when they would be so much nearer
each
other.
While Ocean wrap'd it in his azure robe.
CANTO II. l. 34.
From having observed that many of the highest mountains of the
world
consist of lime-stone replete with shells, and that these mountains
bear
the marks of having been lifted up by subterraneous fires from the
interior parts of the globe; and as lime-stone replete with shells
is
found at the bottom of many of our deepest mines some philosophers
have
concluded that the nucleus of the earth was for many ages covered
with
water which was peopled with its adapted animals; that the shells
and
bones of these animals in a long series of time produced solid
strata in
the ocean surrounding the original nucleus.
These strata consist of the accumulated exuviae of shell-fish, the
animals perished age after age but their shells remained, and in
progression of time produced the amazing quantities of lime-stone
which
almost cover the earth. Other marine animals called coralloids
raised
walls and even mountains by the congeries of their calcareous
habitations, these perpendicular corralline rocks make some parts
of the
Southern Ocean highly dangerous, as appears in the journals of
Capt.
Cook. From contemplating the immense strata of lime-stone, both in
respect to their extent and thickness, formed from these shells of
animals, philosophers have been led to conclude that much of the
water
of the sea has been converted into calcareous earth by passing
through
their organs of digestion. The formation of calcareous earth seems
more
particularly to be an animal process as the formation of clay
belongs to
the vegetable economy; thus the shells of crabs and other
testaceous
fish are annually reproduced from the mucous membrane beneath them;
the
shells of eggs are first a mucous membrane, and the calculi of the
kidneys and those found in all other parts of our system which
sometimes
contain calcareous earth, seem to originate from inflamed
membranes; the
bones themselves consist of calcareous earth united with the
phosphoric
or animal acid, which may be separated by dissolving the ashes of
calcined bones in the nitrous acid; the various secretions of
animals,
as their saliva and urine, abound likewise with calcareous earth,
as
appears by the incrustations about the teeth and the sediments of
urine.
It is probable that animal mucus is a previous process towards the
formation of calcareous earth; and that all the calcareous earth in
the
world which is seen in lime-stones, marbles, spars, alabasters,
marls,
(which make up the greatest part of the earth's crust, as far as it
has
yet been penetrated,) have been formed originally by animal and
vegetable bodies from the mass of water, and that by these means
the
solid part of the terraqueous globe has perpetually been in an
increasing state and the water perpetually in a decreasing one.
After the mountains of shells and other recrements of aquatic
animals
were elevated above the water the upper heaps of them were
gradually
dissolved by rains and dews and oozing through were either
perfectly
crystallized in smaller cavities and formed calcareous spar, or
were
imperfectly crystallized on the roofs of larger cavities and
produced
stalactes; or mixing with other undissolved shells beneath them
formed
marbles, which were more or less crystallized and more or less
pure; or
lastly, after being dissolved, the water was exhaled from them in
such a
manner that the external parts became solid, and forming an arch
prevented the internal parts from approaching each other so near as
to
become solid, and thus chalk was produced. I have specimens of
chalk
formed at the root of several stalactites, and in their central
parts;
and of other stalactites which are hollow like quills from a
similar
cause, viz. from the external part of the stalactite hardening
first by
its evaporation, and thus either attracting the internal dissolved
particles to the crust, or preventing them from approaching each
other
so as to form a solid body. Of these I saw many hanging from the
arched
roof of a cellar under the high street in Edinburgh.
If this dissolved limestone met with vitriolic acid it was
converted
into alabaster, parting at the same time with its fixable air. If
it met
with the fluor acid it became fluor; if with the siliceous acid,
flint;
and when mixed with clay and sand, or either of them, acquires the
name
of marl. And under one or other of these forms composes a great
part of
the solid globe of the earth.
Another mode in which limestone appears is in the form of round
granulated particles, but slightly cohering together; of this kind
a bed
extends over Lincoln heath, perhaps twenty miles long by ten wide.
The
form of this calcareous sand, its angles having been rubbed off,
and the
flatness of its bed, evinces that that part of the country was so
formed
under water, the particles of sand having thus been rounded, like
all
other rounded pebbles. This round form of calcareous sand and of
other
larger pebbles is produced under water, partly by their being more
or
less soluble in water, and hence the angular parts become
dissolved,
first, by their exposing a larger surface to the action of the
menstruum, and secondly, from their attrition against each other by
the
streams or tides, for a great length of time, successively as they
were
collected, and perhaps when some of them had not acquired their
hardest
state.
This calcareous sand has generally been called ketton-stone and
believed
to resemble the spawn of fish, it has acquired a form so much
rounder
than siliceous sand from its being of so much softer a texture and
also
much more soluble in water. There are other soft calcareous stones
called tupha which are deposited from water on mosses, as at
Matlock,
from which moss it is probable the water may receive something
which
induces it the readier to part with its earth.
In some lime-stones the living animals seem to have been buried as
well
as their shells during some great convulsion of nature, these
shells
contain a black coaly substance within them, in others some
phlogiston
or volatile alcali from the bodies of the dead animals remains
mixed
with the stone, which is then called liver-stone as it emits a
sulphurous smell on being struck, and there is a stratum about six
inches thick extends a considerable way over the iron ore at
Wingerworth
near Chesterfield in Derbyshire which seems evidently to have been
formed from the shells of fresh-water muscles.
There is however another source of calcareous earth besides the
aquatic
one above described and that is from the recrements of land animals
and
vegetables as found in marls, which consist of various mixtures of
calcareous earth, sand, and clay, all of them perhaps principally
from
vegetable origin.
Dr. Hutton is of opinion that the rocks of marble have been
softened by
fire into a fluid mass, which he thinks under immense pressure
might be
done without the escape of their carbonic acid or fixed air. Edinb.
Transact. Vol. I. If this ingenious idea be allowed it might
account for
the purity of some white marbles, as during their fluid state there
might be time for their partial impurities, whether from the bodies
of
the animals which produced the shells or from other extraneous
matter,
either to sublime to the uppermost part of the stratum or to
subside to
the lowermost part of it. As a confirmation of this theory of Dr.
Hutton's it may be added that some calcareous stones are found
mixed
with lime, and have thence lost a part of their fixed air or
carbonic
gas, as the bath-stone, and on that account hardens on being
exposed to
the air, and mixed with sulphur produces calcareous liver of
sulphur.
Falconer on Bath-water. Vol. I. p. 156. and p. 257. Mr. Monnet
found
lime in powder in the mountains of Auvergne, and suspected it of
volcanic origin. Kirwan's Min. p. 22.
Gnomes! you then taught transuding dews to pass
Through time-fallen woods, and root-inwove morass.
CANTO II. l. 115.
Where woods have repeatedly grown and perished morasses are in
process
of time produced, and by their long roots fill up the interstices
till
the whole becomes for many yards deep a mass of vegetation. This
fact is
curiously verified by an account given many years ago by the Earl
of
Cromartie, of which the following is a short abstract.
In the year 1651 the EARL OF CROMARTIE being then nineteen years of
age
saw a plain in the parish of Lockburn covered over with a firm
standing
wood, which was so old that not only the trees had no green leaves
upon
them but the bark was totally thrown off, which he was there
informed by
the old countrymen was the universal manner in which fir-woods
terminated, and that in twenty or thirty years the trees would cast
themselves up by the roots. About fifteen years after he had
occasion to
travel the same way and observed that there was not a tree nor the
appearance of a root of any of them; but in their place the whole
plain
where the wood stood was covered with a flat green moss or morass,
and
on asking the country people what was become of the wood he was
informed
that no one had been at the trouble to carry it away, but that it
had
all been overturned by the wind, that the trees lay thick over each
other, and that the moss or bog had overgrown the whole timber,
which
they added was occasioned by the moisture which came down from the
high
hills above it and stagnated upon the plain, and that nobody could
yet
pass over it, which however his Lordship was so incautious as to
attempt
and slipt up to the arm-pits. Before the year 1699 that whole piece
of
ground was become a solid moss wherein the peasants then dug turf
or
peat, which however was not yet of the best sort. Philos. Trans.
No.
330. Abridg. Vol. V. p. 272.
Morasses in great length of time undergo variety of changes, first
by
elutriation, and afterwards by fermentation, and the consequent
heat. 1.
By water perpetually oozing through them the most soluble parts are
first washed away, as the essential salts, these together with the
salts
from animal recrements are carried down the rivers into the sea,
where
all of them seem to decompose each other except the marine salt.
Hence
the ashes of peat contain little or no vegetable alcali and are not
used
in the countries, where peat constitutes the fuel of the lower
people,
for the purpose of washing linen. The second thing which is always
seen
oozing from morasses is iron in solution, which produces chalybeate
springs, from whence depositions of ochre and variety of iron ores.
The
third elutriation seems to consist of vegetable acid, which by
means
unknown appears to be converted into all other acids. 1. Into
marine and
nitrous acids as mentioned above. 2. Into vitriolic acid which is
found
in some morasses so plentifully as to preserve the bodies of
animals
from putrefaction which have been buried in them, and this acid
carried
away by rain and dews and meeting with calcareous earth produces
gypsum
or alabaster, with clay it produces alum, and deprived of its vital
air
produces sulphur. 3. Fluor acid which being washed away and meeting
with
calcareous earth produces fluor or cubic spar. 4. The siliceous
acid
which seems to have been disseminated in great quantity either by
solution in water or by solution in air, and appears to have
produced
the sand in the sea uniting with calcareous earth previously
dissolved
in that element, from which were afterwards formed some of the
grit-
stone rocks by means of a siliceous or calcareous cement. By its
union
with the calcareous earth of the morass other strata of siliceous
sand
have been produced; and by the mixture of this with clay and lime
arose
the beds of marl.
In other circumstances, probably where less moisture has prevailed,
morasses seem to have undergone a fermentation, as other vegetable
matter, new hay for instance is liable to do from the great
quantity of
sugar it contains. From the great heat thus produced in the lower
parts
of immense beds of morass the phlogistic part, or oil, or
asphaltum,
becomes distilled, and rising into higher strata becomes again
condensed
forming coal-beds of greater or less purity according to their
greater
or less quantity of inflammable matter; at the same time the clay
beds
become purer or less so, as the phlogistic part is more or less
completely exhaled from them. Though coal and clay are frequently
produced in this manner, yet I have no doubt, but that they are
likewise
often produced by elutriation; in situations on declivities the
clay is
washed away down into the valleys, and the phlogistic part or coal
left
behind; this circumstance is seen in many valleys near the beds of
rivers, which are covered recently by a whitish impure clay, called
water-clay. See note XIX. XX. and XXIII.
LORD CROMARTIE has furnished another curious observation on
morasses in
the paper above referred to. In a moss near the town of Eglin in
Murray,
though there is no river or water which communicates with the moss,
yet
for three or four feet of depth in the moss there are little
shell-fish
resembling oysters with living fish in them in great quantities,
though
no such fish are found in the adjacent rivers, nor even in the
water
pits in the moss, but only in the solid substance of the moss. This
curious fact not only accounts for the shells sometimes found on
the
surface of coals, and in the clay above them; but also for a thin
stratum of shells which sometimes exists over iron-ore.
Cold waves, immerged, the glowing mass congeal,
And turn to adamant the hissing Steel.
CANTO II. l. 191.
As iron is formed near the surface of the earth, it becomes exposed
to
streams of water and of air more than most other metallic bodies,
and
thence becomes combined with oxygene, or vital air, and appears
very
frequently in its calciform state, as in variety of ochres.
Manganese,
and zinc, and sometimes lead, are also found near the surface of
the
earth, and on that account become combined with vital air and are
exhibited in their calciform state.
The avidity with which iron unites with oxygene, or vital air, in
which
process much heat is given out from the combining materials, is
shewn by
a curious experiment of M. Ingenhouz. A fine iron wire twisted
spirally
is fixed to a cork, on the point of the spire is fixed a match made
of
agaric dipped in solution of nitre; the match is then ignited, and
the
wire with the cork put immediately into a bottle full of vital air,
the
match first burns vividly, and the iron soon takes fire and
consumes
with brilliant sparks till it is reduced to small brittle globules,
gaining an addition of about one third of its weight by its union,
with
vital air. Annales de Chymie. Traite de Chimie, per Lavoisier, c.
iii.
STEEL.
It is probably owing to a total deprivation of vital air which it
holds
with so great avidity, that iron on being kept many hours or days
in
ignited charcoal becomes converted into steel, and thence acquires
the
faculty of being welded when red hot long before it melts, and also
the
power of becoming hard when immersed in cold water; both which I
suppose
depend on the same cause, that is, on its being a worse conductor
of
heat than other metals; and hence the surface both acquires heat
much
sooner, and loses it much sooner, than the internal parts of it, in
this
circumstance resembling glass.
When steel is made very hot, and suddenly immerged in very cold
water,
and moved about in it, the surface of the steel becomes cooled
first,
and thus producing a kind of case or arch over the internal part,
prevents that internal part from contracting quite so much as it
otherwise would do, whence it becomes brittler and harder, like the
glass-drops called Prince Rupert's drops, which are made by
dropping
melted glass into cold water. This idea is countenanced by the
circumstance that hardened steel is specifically lighter than steel
which is more gradually cooled. (Nicholson's Chemistry, p. 313.)
Why the
brittleness and hardness of steel or glass should keep pace or be
companions to each other may be difficult to conceive.
When a steel spring is forcibly bent till it break, it requires
less
power to bend it through the first inch than the second, and less
through the second than the third; the same I suppose to happen if
a
wire be distended till it break by hanging weights to it; this
shews
that the particles may be forced from each other to a small
distance by
less power, than is necessary to make them recede to a greater
distance;
in this circumstance perhaps the attraction of cohesion differs
from
that of gravitation, which exerts its power inversely as the
squares of
the distance. Hence it appears that if the innermost particles of a
steel bar, by cooling the external surface first, are kept from
approaching each other so nearly as they otherwise would do, that
they
become in the situation of the particles on the convex side of a
bent
spring, and can not be forced further from each other except by a
greater power than would have been necessary to have made them
recede
thus far. And secondly, that if they be forced a little further
from
each other they separate; this may be exemplified by laying two
magnetic
needles parallel to each other, the contrary poles together, then
drawing them longitudinally from each other, they will slide with
small
force till they begin to separate, and will then require a stronger
force to really separate them. Hence it appears, that hardness and
brittleness depend on the same circumstance, that the particles are
removed to a greater distance from each other and thus resist any
power
more forcibly which is applied to displace them further, this
constitutes hardness. And secondly, if they are displaced by such
applied force they immediately separate, and this constitutes
brittleness.
Steel may be thus rendered too brittle for many purposes, on which
account artists have means of softening it again, by exposing it to
certain degrees of heat, for the construction of different kinds of
tools, which is called tempering it. Some artists plunge large
tools in
very cold water as soon as they are compleatly ignited, and moving
it
about, take it out as soon as it ceases to be luminous beneath the
water; it is then rubbed quickly with a file or on sand to clean
the
surface, the heat which the metal still retains soon begins to
produce a
succession of colours; if a hard temper be required, the piece is
dipped
again and stirred about in cold water as soon as the yellow tinge
appears, if it be cooled when the purple tinge appears it becomes
fit
for gravers' tools used in working upon metals; if cooled while
blue it
is proper for springs. Nicholson's Chemistry, p. 313. Keir's
Chemical
Dictionary.
MODERN PRODUCTION OF IRON.
The recent production of iron is evinced from the chalybeate waters
which flow from morasses which lie upon gravel-beds, and which must
therefore have produced iron after those gravel-beds were raised
out of
the sea. On the south side of the road between Cheadle and Okeymoor
in
Staffordshire, yellow stains of iron are seen to penetrate the
gravel
from a thin morass on its surface. There is a fissure eight or ten
feet
wide, in a gravel-bed on the eastern side of the hollow road
ascending
the hill about a mile from Trentham in Staffordshire, leading
toward
Drayton in Shropshire, which fissure is filled up with nodules of
iron-
ore. A bank of sods is now raised against this fissure to prevent
the
loose iron nodules from falling into the turnpike road, and thus
this
natural curiosity is at present concealed from travellers. A
similar
fissure in a bed of marl, and filled up with iron nodules and with
some
large pieces of flint, is seen on the eastern side of the hollow
road
ascending the hill from the turnpike house about a mile from Derby
in
the road towards Burton. And another such fissure filled with iron
nodes, appears about half a mile from Newton-Solney in Derbyshire,
in
the road to Burton, near the summit of the hill. These collections
of
iron and of flint must have been produced posterior to the
elevation of
all those hills, and were thence evidently of vegetable or animal
origin. To which should be added, that iron is found in general in
beds
either near the surface of the earth, or stratified with clay coals
or
argillaceous grit, which are themselves productions of the modern
world,
that is, from the recrements of vegetables and air-breathing
animals.
Not only iron but manganese, calamy, and even copper and lead
appear in
some instances to have been of recent production. Iron and
manganese are
detected in all vegetable productions, and it is probable other
metallic
bodies might be found to exist in vegetable or animal matters, if
we had
tests to detect them in very minute quantities. Manganese and
calamy are
found in beds like iron near the surface of the earth, and in a
calciform state, which countenances their modern production. The
recent
production of calamy, one of the ores of zinc, appears from its
frequently incrusting calcareous spar in its descent from the
surface of
the earth into the uppermost fissures of the limestone mountains of
Derbyshire. That the calamy has been carried by its solution or
diffusion in water into these cavities, and not by its ascent from
below
in form of steam, is evinced from its not only forming a crust over
the
dogtooth spar, but by its afterwards dissolving or destroying the
sparry
crystal. I have specimens of calamy in the form of dogtooth spar,
two
inches high, which are hollow, and stand half an inch above the
diminished sparry crystal on which they were formed, like a sheath
a
great deal too big for it; this seems to shew, that this process
was
carried on in water, otherwise after the calamy had incrusted its
spar,
and dissolved its surface, so as to form a hollow cavern over it,
it
could not act further upon it except by the interposition of some
medium. As these spars and calamy are formed in the fissures of
mountains they must both have been formed after the elevation of
those
mountains.
In respect to the recent production of copper, it was before
observed in
note on Canto II. l. 394, that the summit of the grit-stone
mountain at
Hawkstone in Shropshire, is tinged with copper, which from the
appearance of the blue stains seems to have descended to the parts
of
the rock beneath. I have a calciform ore of copper consisting of
the
hollow crusts of cubic cells, which has evidently been formed on
crystals of fluor, which it has eroded in the same manner as the
calamy
erodes the calcareous crystals, from whence may be deduced in the
same
manner, the aqueous solution or diffusion, as well as the recent
production of this calciform ore of copper.
Lead in small quantities is sometimes found in the fissures of
coal-
beds, which fissures are previously covered with spar; and
sometimes in
nodules of iron-ore. Of the former I have a specimen from near
Caulk in
Derbyshire, and of the latter from Colebrook Dale in Shropshire.
Though
all these facts shew that some metallic bodies are formed from
vegetable
or animal recrements, as iron, and perhaps manganese and calamy,
all
which are found near the surface of the earth; yet as the other
metals
are found only in fissures of rocks, which penetrate to unknown
depths,
they may be wholly or in part produced by ascending steams from
subterraneous fires, as mentioned in note on Canto II. l. 398.
SEPTARIA OF IRON-STONE.
Over some lime works at Walsall in Staffordshire, I observed some
years
ago a stratum of iron earth about six inches thick, full of very
large
cavities; these cavities were evidently produced when the material
passed from a semifluid state into a solid one; as the frit of the
potters, or a mixture of clay and water is liable to crack in
drying;
which is owing to the further contraction of the internal part,
after
the crust is become hard. These hollows are liable to receive
extraneous
matter, as I believe gypsum, and sometimes spar, and even lead; a
curious specimen of the last was presented to me by Mr. Darby of
Colebrook Dale, which contains in its cavity some ounces of
lead-ore.
But there are other septaria of iron-stone which seem to have had a
very
different origin, their cavities having been formed in cooling or
congealing from an ignited state, as is ingeniously deduced by Dr.
Hutton from their internal structure. Edinb. Transact. Vol. I. p.
246.
The volcanic origin of these curious septaria appears to me to be
further evinced from their form and the places where they are
found.
They consist of oblate spheroids and are found in many parts of the
earth totally detached from the beds in which they lie, as at East
Lothian in Scotland. Two of these, which now lie before me, were
found
with many others immersed in argillaceous shale or shiver,
surrounded by
broken limestone mountains at Bradbourn near Ashbourn in
Derbyshire, and
were presented to me by Mr. Buxton, a gentleman of that town. One
of
these is about fifteen inches in its equatorial diameter, and about
six
inches in its polar one, and contains beautiful star-like septaria
incrusted and in part filled with calcareous spar. The other is
about
eight inches in its equatorial diameter, and about four inches in
its
polar diameter, and is quite solid, but shews on its internal
surface
marks of different colours, as if a beginning separation had taken
place. Now as these septaria contain fifty per cent, of iron,
according
to Dr. Hutton, they would soften or melt into a semifluid globule
by
subterraneous fire by less heat than the limestone in their
vicinity;
and if they were ejected through a hole or fissure would gain a
circular
motion along with their progressive one by their greater friction
or
adhesion to one side of the hole. This whirling motion would
produce the
oblate spheroidical form which they possess, and which as far as I
know
can not in any other way be accounted for. They would then harden
in the
air as they rose into the colder parts of the atmosphere; and as
they
descended into so soft a material as shale or shiver, their forms
would
not be injured in their fall; and their presence in materials so
different from themselves becomes accounted for.
About the tropics of the large septarium above mentioned, are
circular
eminent lines, such as might have been left if it had been coarsely
turned in a lathe. These lines seem to consist of a fluid matter,
which
seems to have exsuded in circular zones, as their edges appear
blunted
or retracted; and the septarium seems to have split easier in such
sections parallel to its equator. Now as the crust would first
begin to
cool and harden after its ejection in a semifluid state, and the
equatorial diameter would become gradually enlarged as it rose in
the
air; the internal parts being softer would slide beneath the polar
crust, which might crack and permit part of the semifluid to
exsude, and
it is probable the adhesion would thus become less in sections
parallel
to the equator. Which further confirms this idea of the production
of
these curious septaria. A new-cast cannon ball red-hot with its
crust
only solid, if it were shot into the air would probably burst in
its
passage; as it would consist of a more fluid material than these
septaria; and thus by discharging a shower of liquid iron would
produce
more dreadful combustion, if used in war, than could be effected by
a
ball, which had been cooled and was heated again: since in the
latter
case the ball could not have its internal parts made hotter than
the
crust of it, without first loosing its form.
Transmute to glittering flints her chalky lands,
Or sink on Ocean's bed in countless sands.
CANTO II. l. 217.
1. SILICEOUS ROCKS.
The great masses of siliceous sand which lie in rocks upon the beds
of
limestone, or which are stratified with clay, coal, and iron-ore,
are
evidently produced in the decomposition of vegetable or animal
matters,
as explained in the note on morasses. Hence the impressions of
vegetable
roots and even whole trees are often found in sand-stone, as well
as in
coals and iron-ore. In these sand-rocks both the siliceous acid and
the
calcareous base seem to be produced from the materials of the
morass;
for though the presence of a siliceous acid and of a calcareous
base
have not yet been separately exhibited from flints, yet from the
analogy
of flint to fluor, and gypsum, and marble, and from the conversion
of
the latter into flint, there can be little doubt of their
existence.
These siliceous sand-rocks are either held together by a siliceous
cement, or have a greater or less portion of clay in them, which in
some
acts as a cement to the siliceous crystals, but in others is in
such
great abundance that in burning them they become an imperfect
porcelain
and are then used to repair the roads, as at Chesterfield in
Derbyshire;
these are called argillaceous grit by Mr. Kirwan. In other places a
calcareous matter cements the crystals together; and in other
places the
siliceous crystals lie in loose strata under the marl in the form
of
white sand; as at Normington about a mile from Derby.
The lowest beds of siliceous sand-stone produced from morasses seem
to
obtain their acid from the morass, and their calcareous base from
the
limestone on which it rests; These beds possess a siliceous cement,
and
from their greater purity and hardness are used for course
grinding-
stones and scyth stones, and are situated on the edges of limestone
countries, having lost the other strata of coals, or clay, or iron,
which were originally produced above them. Such are the sand-rocks
incumbent on limestone near Matlock in Derbyshire. As these
siliceous
sand-rocks contain no marine productions scattered amongst them,
they
appear to have been elevated, torn to pieces, and many fragments of
them
scattered over the adjacent country by explosions, from fires
within the
morass from which they have been formed; and which dissipated every
thing inflammable above and beneath them, except some stains of
iron,
with which they are in some places spotted. If these sand-rocks had
been
accumulated beneath the sea, and elevated along with the beds of
limestone on which they rest, some vestiges of marine shells either
in
their siliceous or calcareous state must have been discerned
amongst
them.
2. SILICEOUS TREES.
In many of these sand-rocks are found the impressions of vegetable
roots, which seem to have been the most unchangeable parts of the
plant,
as shells and shark's teeth are found in chalk-beds from their
being the
most unchangeable parts of the animal. In other instances the wood
itself is penetrated, and whole trees converted into flint;
specimens of
which I have by me, from near Coventry, and from a gravel-pit in
Shropshire near Child's Archal in the road to Drayton. Other
polished
specimens of vegetable flints abound in the cabinets of the
curious,
which evidently shew the concentric circles of woody fibres, and
their
interstices filled with whiter siliceous matter, with the branching
off
of the knots when cut horizontally, and the parallel lines of wood
when
cut longitudinally, with uncommon beauty and variety. Of these I
possess
some beautiful specimens, which were presented to me by the Earl of
Uxbridge.
The colours of these siliceous vegetables are generally brown, from
the
iron, I suppose, or manganese, which induced them to crystallize or
to
fuse more easily. Some of the cracks of the wood in drying are
filled
with white flint or calcedony, and others of them remain hollow,
lined
with innumerable small crystals tinged with iron, which I suppose
had a
share in converting their calcareous matter into siliceous
crystals,
because the crystals called Peak-diamonds are always found bedded
in an
ochreous earth; and those called Bristol-stones are situated on
limestone coloured with iron. Mr. F. French presented me with a
congeries of siliceous crystals, which he gathered on the crater
(as he
supposes) of an extinguished volcano at Cromach Water in
Cumberland. The
crystals are about an inch high in the shape of dogtooth or
calcareous
spar, covered with a dark ferruginous matter. The bed on which they
rest
is about an inch in thickness, and is stained with iron on its
undersurface. This curious fossil shews the transmutation of
calcareous
earth into siliceous, as much as the siliceous shells which abound
in
the cabinets of the curious. There may sometime be discovered in
this
age of science, a method of thus impregnating wood with liquid
flint,
which would produce pillars for the support, and tiles for the
covering
of houses, which would be uninflammable and endure as long as the
earth
beneath them.
That some siliceous productions have been in a fluid state without
much
heat at the time of their formation appears from the vegetable
flints
above described not having quite lost their organized appearance;
from
shells, and coralloids, and entrochi being converted into flint
without
loosing their form; from the bason of calcedony round Giesar in
Iceland;
and from the experiment of Mr. Bergman, who obtained thirteen
regular
formed crystals by suffering the powder of quartz to remain in a
vessel
with fluor acid for two years; these crystals were about the size
of
small peas, and were not so hard as quartz. Opusc. de Terra
Silicea, p.
33. Mr. Achard procured both calcareous and siliceous crystals, one
from
calcareous earth, and the other from the earth of alum, both
dissolved
in water impregnated with fixed air; the water filtrating very
slowly
through a porous bottom of baked clay. See Journal de Physique, for
January, 1778.
3. AGATES, ONYXES, SCOTS-PEBBLES.
In small cavities of these sand-rocks, I am informed, the beautiful
siliceous nodules are found which are called Scot's-pebbles; and
which
on being cut in different directions take the names of agates,
onyxes,
sardonyxes, &c. according to the colours of the lines or strata
which
they exhibit. Some of the nodules are hollow and filled with
crystals,
others have a nucleus of less compact siliceous matter which is
generally white, surrounded with many concentric strata coloured
with
iron, and other alternate strata of white agate or calcedony,
sometimes
to the number of thirty.
I think these nodules bear evident marks of their having been in
perfect
fusion by either heat alone, or by water and heat, under great
pressure,
according to the ingenious theory of Dr. Hutton; but I do not
imagine,
that they were injected into cavities from materials from without,
but
that some vegetables or parts of vegetables containing more iron or
manganese than others, facilitated the compleat fusion, thus
destroying
the vestiges of vegetable organization, which were conspicuous in
the
siliceous trees above mentioned. Some of these nodules being hollow
and
lined with crystals, and others containing a nucleus of white
siliceous
matter of a looser texture, shew they were composed of the
materials
then existing in the cavity; which consisting before of loose sand,
must
take up less space when fused into a solid mass.
These siliceous nodules resemble the nodules of iron-stone
mentioned in
note on Canto II. l. 183, in respect to their possessing a great
number
of concentric spheres coloured generally with iron, but they differ
in
this circumstance, that the concentric spheres generally obey the
form
of the external crust, and in their not possessing a chalybeate
nucleus.
The stalactites formed on the roofs of caverns are often coloured
in
concentric strata, by their coats being spread over each other at
different times; and some of them, as the cupreous ones, possess
great
beauty from this formation; but as these are necessarily more or
less of
a cylindrical or conic form, the nodules or globular flints above
described cannot have been constructed in this manner. To what law
of
nature then is to be referred the production of such numerous
concentric
spheres? I suspect to the law of congelation.
When salt and water are exposed to severe frosty air, the salt is
said
to be precipitated as the water freezes; that is, as the heat, in
which
it was dissolved, is withdrawn; where the experiment is tried in a
bowl
or bason, this may be true, as the surface freezes first, and the
salt
is found at the bottom. But in a fluid exposed in a thin phial, I
found
by experiment, that the extraneous matter previously dissolved by
the
heat in the mixture was not simply set at liberty to subside, but
was
detruded or pushed backward as the ice was produced. The experiment
was
this: about two ounces of a solution of blue vitriol were
accidentally
frozen in a thin phial, the glass was cracked and fallen to pieces,
the
ice was dissolved, and I found a pillar of blue vitriol standing
erect
on the bottom of the broken bottle. Nor is this power of
congelation
more extraordinary, than that by its powerful and sudden expansion
it
should burst iron shells and coehorns, or throw out the plugs with
which
the water was secured in them above one hundred and thirty yards,
according to the experiments at Quebec by Major Williams. Edinb.
Transact. Vol. II. p. 23.
In some siliceous nodules which now lie before me, the external
crust
for about the tenth of an inch consists of white agate, in others
it is
much thinner, and in some much thicker; corresponding with this
crust
there are from twenty to thirty superincumbent strata, of
alternately
darker and lighter colour; whence it appears, that the external
crust as
it cooled or froze, propelled from it the iron or manganese which
was
dissolved in it; this receded till it had formed an arch or vault
strong
enough to resist its further protrusion; then the next inner sphere
or
stratum as it cooled or froze, propelled forwards its colouring
matter
in the same manner, till another arch or sphere produced sufficient
resistance to this frigoriscent expulsion. Some of them have
detruded
their colouring matter quite to the centre, the rings continuing to
become darker as they are nearer it; in others the chalybeate arch
seems
to have stopped half an inch from the centre, and become thicker by
having attracted to itself the irony matter from the white nucleus,
owing probably to its cooling less precipitately in the central
parts
than at the surface of the pebble.
A similar detrusion of a marly matter in circular arches or vaults
obtains in the salt mines in Cheshire; from whence Dr. Hutton very
ingeniously concludes, that the salt must have been liquified by
heat;
which would seem to be much confirmed by the above theory. Edinb.
Transact. Vol. I. p. 244.
I cannot conclude this account of Scots-pebbles without observing
that
some of them on being sawed longitudinally asunder, seem still to
possess some vestiges of the cylindrical organization of
vegetables;
others possess a nucleus of white agate much resembling some
bulbous
roots with their concentric coats, or the knots in elm-roots or
crab-
trees; some of these I suppose were formed in the manner above
explained, during the congelation of masses of melted flint and
iron;
others may have been formed from a vegetable nucleus, and retain
some
vestiges of the organization of the plant.
4. SAND OF THE SEA.
The great abundance of siliceous sand at the bottom of the ocean
may in
part be washed down from the siliceous rocks above described, but
in
general I suppose it derives its acid only from the vegetable and
animal
matter of morasses, which is carried down by floods or by the
atmosphere, and becomes united in the sea with its calcareous base
from
shells and coralloids, and thus assumes its crystalline form at the
bottom of the ocean, and is there intermixed with gravel or other
matters washed from the mountains in its vicinity.
5. CHERT, OR PETROSILEX.
The rocks of marble are often alternately intermixed with strata of
chert, or coarse flint, and this in beds from one to three feet
thick,
as at Ham and Matlock, or of less than the tenth of an inch in
thickness, as a mile or two from Bakewell in the road to Buxton. It
is
difficult to conceive in what manner ten or twenty strata of either
limestone or flint, of different shades of white and black, could
be
laid quite regularly over each other from sediments or
precipitations
from the sea; it appears to me much easier to comprehend, by
supposing
with Dr. Hutton, that both the solid rocks of marble and the flint
had
been fused by great heat, (or by heat and water,) under immense
pressure; by its cooling or congealing the colouring matter might
be
detruded, and form parallel or curvilinean strata, as above
explained.
The colouring matter both of limestone and flint was probably owing
to
the flesh of peculiar animals, as well as the siliceous acid, which
converted some of the limestone into flint; or to some strata of
shell-
fish having been overwhelmed when alive with new materials, while
others
dying in their natural situations would lose their fleshy parts,
either
by its putrid solution in the water or by its being eaten by other
sea-
insects. I have some calcareous fossil shells which contain a black
coaly matter in them, which was evidently the body of the animal,
and
others of the same kind filled with spar instead of it. The
Labradore
stone has I suppose its colours from the nacre or mother-pearl
shells,
from which it was probably produced. And there is a stratum of
calcareous matter about six or eight inches thick at Wingerworth in
Derbyshire over the iron-beds, which is replete with shells of
fresh-
water muscles, and evidently obtains its dark colour from them, as
mentioned in note XVI. Many nodules of flint resemble in colour as
well
as in form the shell of the echinus or sea-urchin; others resemble
some
coralloids both in form and colour; and M. Arduini found in the
Monte de
Pancrasio, red flints branching like corals, from whence they seem
to
have obtained both their form and their colour. Ferber's Travels in
Italy, p. 42.
6. NODULES OF FLINT IN CHALK-BEDS.
As the nodules of flint found in chalk-beds possess no marks of
having
been rounded by attrition or solution, I conclude that they have
gained
their form as well as their dark colour from the flesh of the
shell-fish
from which they had their origin; but which have been so compleatly
fused by heat, or heat and water, as to obliterate all vestiges of
the
shell, in the same manner as the nodules of agate and onyx were
produced
from parts of vegetables, but which had been so completely fused as
to
obliterate all marks of their organization, or as many iron-nodules
have
obtained their form and origin from peculiar vegetables.
Some nodules in chalk-beds consist of shells of echini filled up
with
chalk, the animal having been dissolved away by putrescence in
water, or
eaten by other sea-insects; other shells of echini, in which I
suppose
the animal's body remained, are converted into flint but still
retain
the form of the shell. Others, I suppose as above, being more
completely
fused, have become flint coloured by the animal flesh, but without
the
exact form either of the flesh or shell of the animal. Many of
these are
hollow within and lined with crystals, like the Scot's-pebbles
above
described; but as the colouring matter of animal bodies differs but
little from each other compared with those of vegetables, these
flints
vary less in their colours than those above mentioned. At the same
time
as they cooled in concentric spheres like the Scot's-pebbles, they
often
possess faint rings of colours, and always break in conchoide forms
like them.
This idea of the production of nodules of flint in chalk-beds is
countenanced from the iron which generally appears as these flints
become decomposed by the air; which by uniting with the iron in
their
composition reduces it from a vitrescent state to that of calx, and
thus
renders it visible. And secondly, by there being no appearance in
chalk-
beds of a string or pipe of siliceous matter connecting one nodule
with
another, which must have happened if the siliceous matter, or its
acid,
had been injected from without according to the idea of Dr. Hutton.
And
thirdly, because many of them have very large cavities at their
centres,
which should not have happened had they been formed by the
injection of
a material from without.
When shells or chalk are thus converted from calcareous to
siliceous
matter by the flesh of the animal, the new flint being heavier than
the
shell or chalk occupies less space than the materials it was
produced
from; this is the cause of frequent cavities within them, where the
whole mass has not been completely fused and pressed together. In
Derbyshire there are masses of coralloid and other shells which
have
become siliceous, and are thus left with large vacuities sometimes
within and sometimes on the outside of the remaining form of the
shell,
like the French millstones, and I suppose might serve the same
purpose;
the gravel of the Derwent is full of specimens of this kind.
Since writing the above I have received a very ingenious account of
chalk-beds from Dr. MENISH of Chelmsford. He distinguishes
chalk-beds
into three kinds; such as have been raised from the sea with little
disturbance of their strata, as the cliffs of Dover and Margate,
which
he terms intire chalk. Another state of chalk is where it
has suffered
much derangement, as the banks of the Thames at Gravesend and
Dartford.
And a third state where fragments of chalk have been rounded by
water,
which he terms alluvial chalk. In the first of these
situations of
chalk he observes, that the flint lies in strata horizontally,
generally
in distinct nodules, but that he has observed two instances of
solid
plates or strata of flint, from an inch to two inches in thickness,
interposed between the chalk-beds; one of these is in a chalk-bank
by
the road side at Berkhamstead, the other in a bank on the road from
Chatham leading to Canterbury. Dr. Menish has further observed,
that
many of the echini are crushed in their form, and yet filled with
flint,
which has taken the form of the crushed shell, and that though many
flint nodules are hollow, yet that in some echini the siliceum
seems to
have enlarged, as it passed from a fluid to a solid state, as it
swells
out in a protuberance at the mouth and anus of the shell, and that
though these shells are so filled with flint yet that in many
places the
shell itself remains calcareous. These strata of nodules and plates
of
flint seem to countenance their origin from the flesh of a stratum
of
animals which perished by some natural violence, and were buried in
their shells.
7. ANGLES OF SILICEOUS SAND.
In many rocks of siliceous sand the particles retain their angular
form,
and in some beds of loose sand, of which there is one of
considerable
purity a few yards beneath the marl at Normington about a mile
south of
Derby. Other siliceous sands have had their angles rounded off,
like the
pebbles in gravel-beds. These seem to owe their globular form to
two
causes; one to their attrition against each other, when they may
for
centuries have lain at the bottom of the sea, or of rivers; where
they
may have been progressively accumulated, and thus progressively at
the
same time rubbed upon each other by the dashing of the water, and
where
they would be more easily rolled over each other by their gravity
being
so much less than in air. This is evidently now going on in the
river
Derwent, for though there are no limestone rocks for ten or fifteen
miles above Derby, yet a great part of the river-gravel at Derby
consists of limestone nodules, whose angles are quite worn off in
their
descent down the stream.
There is however another cause which must have contributed to round
the
angles both of calcareous and siliceous fragments; and that is,
their
solubility in water; calcareous earth is perpetually found
suspended in
the waters which pass over it; and the earth of flints was observed
by
Bergman to be contained in water in the proportion of one grain to
a
gallon. Kirwan's Mineralogy, p. 107. In boiling water, however, it
is
soluble in much greater proportion, as appears from the siliceous
earth
sublimed in the distillation of fluor acid in glass vessels; and
from
the basons of calcedony which surrounded the jets of hot water near
mount Heccla in Iceland. Troil on Iceland. It is probable most
siliceous
sands or pebbles have at some ages of the world been long exposed
to
aqueous steams raised by subterranean fires. And if fragments of
stone
were long immersed in a fluid menstrum, their angular parts would
be
first dissolved, on account of their greater surface.
Many beds of siliceous gravel are cemented together by a siliceous
cement, and are called breccia; as the plumb-pudding stones of
Hartfordshire, and the walls of a subterraneous temple excavated by
Mr.
Curzon, at Hagley near Rugely in Staffordfshire; these may have
been
exposed to great heat as they were immersed in water; which water
under
great pressure of superincumbent materials may have been rendered
red-
hot, as in Papin's digester; and have thus possessed powers of
solution
with which we are unacquainted.
8. BASALTES AND GRANITES.
Another source of siliceous stones is from the granite, or
basaltes, or
porphyries, which are of different hardnesses according to the
materials
of their composition, or to the fire they have undergone; such are
the
stones of Arthur's-hill near Edinburgh, of the Giant's Causway in
Ireland, and of Charnwood Forest in Leicestershire; the uppermost
stratum of which last seems to have been cracked either by its
elevation, or by its hastily cooling after ignition by the contact
of
dews or snows, and thus breaks into angular fragments, such as the
streets of London are paved with; or have had their angles rounded
by
attrition or by partial solution; and have thus formed the common
paving
stones or bowlers; as well as the gravel, which is often rolled
into
strata amid the siliceous sand-beds, which are either formed or
collected in the sea.
In what manner such a mass of crystallized matter as the Giant's
Causway
and similar columns of basaltes, could have been raised without
other
volcanic appearances, may be a matter not easy to comprehend; but
there
is another power in nature besides that of expansile vapour which
may
have raised some materials which have previously been in igneous or
aqueous solution; and that is the act of congelation. When the
water in
the experiments above related of Major Williams had by congelation
thrown out the plugs from the bomb-shells, a column of ice rose
from the
hole of the bomb six or eight inches high. Other bodies I suspect
increase in bulk which crystallize in cooling, as iron and
type-metal. I
remember pouring eight or ten pounds of melted brimstone into a pot
to
cool and was surprized to see after a little time a part of the
fluid
beneath break a hole in the congealed crust above it, and gradually
rise
into a promontory several inches high; the basaltes has many marks
of
fusion and of crystallization and may thence, as well as many other
kinds of rocks, as of spar, marble, petrosilex, jasper, &c. have
been
raised by the power of congelation, a power whose quantity has not
yet
been ascertained, and perhaps greater and more universal than that
of
vapours expanded by heat. These basaltic columns rise sometimes out
of
mountains of granite itself, as mentioned by Dr. Beddoes, (Phil.
Transact. Vol. LXXX.) and as they seem to consist of similar
materials
more completely fused, there is still greater reason to believe
them to
have been elevated in the cooling or crystallization of the mass.
See
note XXIV.
Whence ductile Clays in wide expansion spread,
Soft as the Cygnet's down, their snow-white bed.
CANTO II. l. 277.
The philosophers, who have attended to the formation of the earth,
have
acknowledged two great agents in producing the various changes
which the
terraqueous globe has undergone, and these are water and fire. Some
of
them have perhaps ascribed too much to one of these great agents of
nature, and some to the other. They have generally agreed that the
stratification of materials could only be produced from sediments
or
precipitations, which were previously mixed or dissolved in the
sea; and
that whatever effects were produced by fire were performed
afterwards.
There is however great difficulty in accounting for the universal
stratification of the solid globe of the earth in this manner,
since
many of the materials, which appear in strata, could not have been
suspended in water; as the nodules of flint in chalk-beds, the
extensive
beds of shells, and lastly the strata of coal, clay, sand, and
iron-ore,
which in most coal-countries lie from five to seven times
alternately
stratified over each other, and none of them are soluble in water.
Add
to this if a solution of them or a mixture of them in water could
be
supposed, the cause of that solution must cease before a
precipitation
could commence.
1. The great masses of lava, under the various names of granite,
porphyry, toadstone, moor-stone, rag, and slate, which constitute
the
old world, may have acquired the stratification, which some of them
appear to possess, by their having been formed by successive
eruptions
of a fluid mass, which at different periods of antient time arose
from
volcanic shafts and covered each other, the surface of the interior
mass
of lava would cool and become solid before the superincumbent
stratum
was poured over it; to the same cause may be ascribed their
different
compositions and textures, which are scarcely the same in any two
parts
of the world.
2. The stratifications of the great masses of limestone, which were
produced from sea-shells, seem to have been formed by the different
times at which the innumerable shells were produced and deposited.
A
colony of echini, or madrepores, or cornua ammonis, lived and
perished
in one period of time; in another a new colony of either similar or
different shells lived and died over the former ones, producing a
stratum of more recent shell over a stratum of others which had
began to
petrify or to become marble; and thus from unknown depths to what
are
now the summits of mountains the limestone is disposed in strata of
varying solidity and colour. These have afterwards undergone
variety of
changes by their solution and deposition from the water in which
they
were immersed, or from having been exposed to great heat under
great
pressure, according to the ingenious theory of Dr. Hutton. Edinb.
Transact. Vol. I. See Note XVI.
3. In most of the coal-countries of this island there are from five
to
seven beds of coal stratified with an equal number of beds, though
of
much greater thickness, of clay and sandstone, and occasionally of
iron-
ores. In what manner to account for the stratification of these
materials seems to be a problem of greater difficulty. Philosophers
have
generally supposed that they have been arranged by the currents of
the
sea; but considering their insolubility in water, and their almost
similar specific gravity, an accumulation of them in such distinct
beds
from this cause is altogether inconceiveable, though some
coal-countries
bear marks of having been at some time immersed beneath the waves
and
raised again by subterranean fires.
The higher and lower parts of morasses were necessarily produced at
different periods of time, see Note XVII. and would thus originally
be
formed in strata of different ages. For when an old wood perished,
and
produced a morass, many centuries would elapse before another wood
could
grow and perish again upon the same ground, which would thus
produce a
new stratum of morass over the other, differing indeed principally
in
its age, and perhaps, as the timber might be different, in the
proportions of its component parts.
Now if we suppose the lowermost stratum of a morass become ignited,
like
fermenting hay, (after whatever could be carried away by solution
in
water was gone,) what would happen? Certainly the inflammable part,
the
oil, sulphur, or bitumen, would burn away, and be evaporated in
air; and
the fixed parts would be left, as clay, lime, and iron; while some
of
the calcareous earth would join with the siliceous acid, and
produce
sand, or with the argillaceous earth, and produce marl. Thence
after
many centuries another bed would take fire, but with less degree of
ignition, and with a greater body of morass over it, what then
would
happen? The bitumen and sulphur would rise and might become
condensed
under an impervious stratum, which might not be ignited, and there
form
coal of different purities according to its degree of fluidity,
which
would permit some of the clay to subside through it into the place
from
which it was sublimed.
Some centuries afterwards another similar process might take place,
and
either thicken the coal-bed, or produce a new clay-bed, or marl, or
sand, or deposit iron upon it, according to the concomitant
circumstances above mentioned.
I do not mean to contend that a few masses of some materials may
not
have been rolled together by currents, when the mountains were much
more
elevated than at present, and in consequence the rivers broader and
more
rapid, and the storms of rain and wind greater both in quantity and
force. Some gravel-beds may have been thus washed from the
mountains;
and some white clay washed from morasses into valleys beneath them;
and
some ochres of iron dissolved and again deposited by water; and
some
calcareous depositions from water, (as the bank for instance on
which
stand the houses at Matlock-bath;) but these are of small extent or
consequence compared to the primitive rocks of granite or porpyhry
which
form the nucleus of the earth, or to the immense strata of
limestone
which crust over the greatest part of this granite or porphyry; or
lastly to the very extensive beds of clay, marl, sandstone, coal,
and
iron, which were probably for many millions of years the only parts
of
our continents and islands, which were then elevated above the
level of
the sea, and which on that account became covered with vegetation,
and
thence acquired their later or superincumbent strata, which
constitute,
what some have termed, the new world.
There is another source of clay, and that of the finest kind, from
decomposed granite, this is of a snowy white and mixed with mining
particles of mica, of this kind is an earth from the country of
Cherokees. Other kinds are from less pure lavas; Mr. Ferber asserts
that
the sulphurous steams from Mount Vesuvius convert the lava into
clay.
“The lavas of the antient Solfatara volcano have been undoubtedly
of a
vitreous nature, and these appear at present argillaceous. Some
fragments of this lava are but half or at one side changed into
clay,
which either is viscid or ductile, or hard and stoney. Clays by
fire are
deprived of their coherent quality, which cannot be restored to
them by
pulverization, nor by humectation. But the sulphureous Solfatara
steams
restore it, as may be easily observed on the broken pots wherein
they
gather the sal ammoniac; though very well baked and burnt at Naples
they
are mollified again by the acid steams into a viscid clay which
keeps
the former fire-burnt colour.” Travels in Italy, p. 156.
Smear'd her huge dragons with metallic hues,
With golden purples, and cobaltic blues;
CANTO II. l. 287.
The fine bright purples or rose colours which we see on china cups
are
not producible with any other material except gold, manganese
indeed
gives a purple but of a very different kind.
In Europe the application of gold to these purposes appears to be
of
modern invention. Cassius's discovery of the precipitate of gold by
tin,
and the use of that precipitate for colouring glass and enamels,
are now
generally known, but though the precipitate with tin be more
successful
in producing the ruby glass, or the colourless glass which becomes
red
by subsequent ignition, the tin probably contributing to prevent
the
gold from separating, (which it is very liable to do during the
fusion;
yet, for enamels, the precipitates made by alcaline salts answer
equally
well, and give a finer red, the colour produced by the tin
precipitate
being a bluish purple, but with the others a rose red. I am
informed
that some of our best artists prefer aurum fulminans, mixing it,
before
it has become dry, with the white composition or enamel flux; when
once
it is divided by the other matter, it is ground with great safety,
and
without the least danger of explosion, whether moist or dry. The
colour
is remarkably improved and brought forth by long grinding, which
accordingly makes an essential circumstance in the process.
The precipitates of gold, and the colcothar or other red
preparations of
iron, are called tender colours. The heat must be no greater
than is
just sufficient to make the enamel run upon the piece, for if
greater,
the colours will be destroyed or changed to a different kind. When
the
vitreous matter has just become fluid it seems as if the coloured
metallic calx remained barely intermixed with it, like a
coloured
powder of exquisite tenuity suspended in water: but by stronger
fire the
calx is dissolved, and metallic colours are altered by
solution in
glass as well as in acids or alcalies.
The Saxon mines have till very lately almost exclusively supplied
the
rest of Europe with cobalt, or rather with its preparations, zaffre
and
smalt, for the exportation of the ore itself is there a capital
crime.
Hungary, Spain, Sweden, and some other parts of the continent, are
now
said to afford cobalts equal to the Saxon, and specimens have been
discovered in our own island, both in Cornwall and in Scotland; but
hitherto in no great quantity.
Calces of cobalt and of copper differ very materially from those
above
mentioned in their application for colouring enamels. In those the
calx
has previously acquired the intended colour, a colour which bears a
red
heat without injury, and all that remains is to fix it on the piece
by a
vitreous flux. But the blue colour of cobalt, and the green or
bluish
green of copper, are produced by vitrification, that is, by
solution
in the glass, and a strong fire is necessary for their perfection.
These
calces therefore, when mixed with the enamel flux, are melted in
crucibles, once or oftener, and the deep coloured opake glass,
thence
resulting, is ground into unpalpable powder, and used for enamel.
One
part of either of these calces is put to ten, sixteen, or twenty
parts
of the flux, according to the depth of colour required. The heat of
the
enamel kiln is only a full red, such as is marked on Mr. Wedgwood's
thermometer 6 degrees. It is therefore necessary that the flux be
so
adjusted as to melt in that low heat. The usual materials are
flint, or
flint-glass, with a due proportion of red-led, or borax, or both,
and
sometimes a little tin calx to give opacity.
Ka-o-lin is the name given by the Chinese to their porcelain
clay, and
pe-tun-tse to the other ingredient in their China ware.
Specimens of
both these have been brought into England, and found to agree in
quality
with some of our own materials. Kaolin is the very same with the
clay
called in Cornwall [Transcriber's note: word missing] and the
petuntse
is a granite similar to the Cornish moorstone. There are
differences,
both in the Chinese petuntses, and the English moorstones; all of
them
contain micaceous and quartzy particles, in greater or less
quantity,
along with feltspat, which last is the essential ingredient for the
porcelain manufactory. The only injurious material commonly found
in
them is iron, which discolours the ware in proportion to its
quantity,
and which our moorstones are perhaps more frequently tainted with
than
the Chinese. Very fine porcelain has been made from English
materials
but the nature of the manufacture renders the process precarious
and the
profit hazardous; for the semivitrification, which constitutes
porcelain, is necessarily accompanied with a degree of softness, or
semifusion, so that the vessels are liable to have their forms
altered
in the kiln, or to run together with any accidental augmentations
of the
fire.
Or bid Mortality rejoice or mourn
O'er the fine forms of Portland's mystic urn.
CANTO II. l. 319.
The celebrated funereal vase, long in possession of the Barberini
family, and lately purchased by the Duke of Portland for a thousand
guineas, is about ten inches high and six in diameter in the
broadest
part. The figures are of most exquisite workmanship in bas relief
of
white opake glass, raised on a ground of deep blue glass, which
appears
black except when held against the light. Mr. Wedgwood is of
opinion
from many circumstances that the figures have been made by cutting
away
the external crust of white opake glass, in the manner the finest
cameo's have been produced, and that it must thence have been the
labour
of a great many years. Some antiquarians have placed the time of
its
production many centuries before the christian aera; as sculpture
was
said to have been declining in respect to its excellence in the
time of
Alexander the Great. See an account of the Barberini or Portland
vase by
M. D'Hancarville, and by Mr. Wedgwood.
Many opinions and conjectures have been published concerning the
figures
on this celebrated vase. Having carefully examined one of Mr.
Wedgwood's
beautiful copies of this wonderful production of art, I shall add
one
more conjecture to the number.
Mr. Wedgwood has well observed that it does not seem probable that
the
Portland vase was purposely made for the ashes of any particular
person
deceased, because many years must have been necessary for its
production. Hence it may be concluded, that the subject of its
embellishments is not private history but of a general nature. This
subject appears to me to be well chosen, and the story to be finely
told; and that it represents what in antient times engaged the
attention
of philosophers, poets, and heroes, I mean a part of the Eleusinian
mysteries.
These mysteries were invented in Aegypt, and afterwards transferred
to
Greece, and flourished more particularly at Athens, which was at
the
same time the seat of the fine arts. They consisted of scenical
exhibitions representing and inculcating the expectation of a
future
life after death, and on this account were encouraged by the
government,
insomuch that the Athenian laws punished a discovery of their
secrets
with death. Dr. Warburton has with great learning and ingenuity
shewn
that the descent of Aeneas into hell, described in the Sixth Book
of
Virgil, is a poetical account of the representations of the future
state
in the Eleusinian mysteries. Divine Legation, Vol. I. p. 210.
And though some writers have differed in opinion from Dr. Warburton
on
this subject, because Virgil has introduced some of his own heroes
into
the Elysian fields, as Deiphobus, Palinurus, and Dido, in the same
manner as Homer had done before him, yet it is agreed that the
received
notions about a future state were exhibited in these mysteries, and
as
these poets described those received notions, they may be said, as
far
as these religious doctrines were concerned, to have described the
mysteries.
Now as these were emblematic exhibitions they must have been as
well
adapted to the purposes of sculpture as of poetry, which indeed
does not
seem to have been uncommon, since one compartment of figures in the
sheild of Aeneas represented the regions of Tartarus. Aen. Lib. X.
The
procession of torches, which according to M. De St. Croix was
exhibited
in these mysteries, is still to be seen in basso relievo,
discovered by
Spon and Wheler. Memoires sur le Mysteres par De St. Croix. 1784.
And it
is very probable that the beautiful gem representing the marriage
of
Cupid and Psyche, as described by Apuleus, was originally
descriptive of
another part of the exhibitions in these mysteries, though
afterwards it
became a common subject of antient art. See Divine Legat. Vol. I.
p.
323. What subject could have been imagined so sublime for the
ornaments
of a funereal urn as the mortality of all things and their
resuscitation? Where could the designer be supplied with emblems
for
this purpose, before the Christian era, but from the Eleusinian
mysteries?
1. The exhibitions of the mysteries were of two kinds, those which
the
people were permitted to see, and those which were only shewn to
the
initiated. Concerning the latter, Aristides calls them “the most
shocking and most ravishing representations.” And Stoboeus asserts
that
the initiation into the grand mysteries exactly resembles death.
Divine
Legat. Vol. I. p. 280, and p. 272. And Virgil in his entrance to
the
shades below, amongst other things of terrible form, mentions
death.
Aen. VI. This part of the exhibition seems to be represented in one
of
the compartments of the Portland vase.
Three figures of exquisite workmanship are placed by the side of a
ruined column whose capital is fallen off, and lies at their feet
with
other disjointed stones, they sit on loose piles of stone beneath a
tree, which has not the leaves of any evergreen of this climate,
but may
be supposed to be an elm, which Virgil places near the entrance of
the
infernal regions, and adds, that a dream was believed to dwell
under
every leaf of it. Aen. VI. l. 281. In the midst of this group
reclines a
female figure in a dying attitude, in which extreme languor is
beautifully represented, in her hand is an inverted torch, an
antient
emblem of extinguished life, the elbow of the same arm resting on a
stone supports her as she sinks, while the other hand is raised and
thrown over her drooping head, in some measure sustaining it and
gives
with great art the idea of fainting lassitude. On the right of her
sits
a man, and on the left a woman, both supporting themselves on their
arms, as people are liable to do when they are thinking intensely.
They
have their backs towards the dying figure, yet with their faces
turned
towards her, as if seriously contemplating her situation, but
without
stretching out their hands to assist her.
This central figure then appears to me to be an hieroglyphic or
Eleusinian emblem of MORTAL LIFE, that is, the lethum, or death,
mentioned by Virgil amongst the terrible things exhibited at the
beginning of the mysteries. The inverted torch shews the figure to
be
emblematic, if it had been designed to represent a real person in
the
act of dying there had been no necessity for the expiring torch, as
the
dying figure alone would have been sufficiently intelligible;—it
would
have been as absurd as to have put an inverted torch into the hand
of a
real person at the time of his expiring. Besides if this figure had
represented a real dying person would not the other figures, or one
of
them at least, have stretched out a hand to support her, to have
eased
her fall among loose stones, or to have smoothed her pillow? These
circumstances evince that the figure is an emblem, and therefore
could
not be a representation of the private history of any particular
family
or event.
The man and woman on each side of the dying figure must be
considered as
emblems, both from their similarity of situation and dress to the
middle
figure, and their being grouped along with it. These I think are
hieroglyphic or Eleusinian emblems of HUMANKIND, with their backs
toward
the dying figure of MORTAL LIFE, unwilling to associate with her,
yet
turning back their serious and attentive countenances, curious
indeed to
behold, yet sorry to contemplate their latter end. These figures
bring
strongly to one's mind the Adam and Eve of sacred writ, whom some
have
supposed to have been allegorical or hieroglyphic persons of
Aegyptian
origin, but of more antient date, amongst whom I think is Dr.
Warburton.
According to this opinion Adam and Eve were the names of two
hieroglyphic figures representing the early state of mankind; Abel
was
the name of an hieroglyphic figure representing the age of
pasturage,
and Cain the name of another hieroglyphic symbol representing the
age of
agriculture, at which time the uses of iron were discovered. And as
the
people who cultivated the earth and built houses would increase in
numbers much faster by their greater production of food, they would
readily conquer or destroy the people who were sustained by
pasturage,
which was typified by Cain slaying Abel.
2. On the other compartment of this celebrated vase is exhibited an
emblem of immortality, the representation of which was well known
to
constitute a very principal part of the shews at the Eleusinian
mysteries, as Dr. Warburton has proved by variety of authority. The
habitation of spirits or ghosts after death was supposed by the
antients
to be placed beneath the earth, where Pluto reigned, and dispensed
rewards or punishments. Hence the first figure in this group is of
the
MANES or GHOST, who having passed through an open portal is
descending
into a dusky region, pointing his toe with timid and unsteady step,
feeling as it were his way in the gloom. This portal Aeneas enters,
which is described by Virgil,—patet atri janua ditis, Aen. VI. l.
126;
as well as the easy descent,—facilis descensus Averni. Ib. The
darkness
at the entrance to the shades is humorously described by Lucian.
Div.
Legat. Vol. I. p. 241. And the horror of the gates of hell was in
the
time of Homer become a proverb; Achilles says to Ulysses, “I hate a
liar
worse than the gates of hell;” the same expression is used in
Isaiah,
ch. xxxviii. v. 10. The MANES or GHOST appears lingering and
fearful,
and wishes to drag after him a part of his mortal garment, which
however
adheres to the side of the portal through which he has passed. The
beauty of this allegory would have been expressed by Mr. Pope, by
“We
feel the ruling passion strong in death.”
A little lower down in the group the manes or ghost is received by
a
beautiful female, a symbol of IMMORTAL LIFE. This is evinced by her
fondling between her knees a large and playful serpent, which from
its
annually renewing its external skin has from great antiquity, even
as
early as the fable of Prometheus, been esteemed an emblem of
renovated
youth. The story of the serpent acquiring immortal life from the
ass of
Prometheus, who carried it on his back, is told in Bacon's Works,
Vol.
V. p. 462. Quarto edit. Lond. 1778. For a similar purpose a serpent
was
wrapped round the large hieroglyphic egg in the temple of Dioscuri,
as
an emblem of the renewal of life from a state of death. Bryant's
Mythology, Vol II. p. 359. sec. edit. On this account also the
serpent
was an attendant on Aesculapius, which seems to have been the name
of
the hieroglyphic figure of medicine. This serpent shews this figure
to
be an emblem, as the torch shewed the central figure of the other
compartment to be an emblem, hence they agreeably correspond, and
explain each other, one representing MORTAL LIFE, and the other
IMMORTAL
LIFE.
This emblematic figure of immortal life sits down with her feet
towards
the figure of Pluto, but, turning back her face towards the timid
ghost,
she stretches forth her hand, and taking hold of his elbow,
supports his
tottering steps, as well as encourages him to advance, both which
circumstances are thus with wonderful ingenuity brought to the eye.
At
the same time the spirit loosely lays his hand upon her arm, as one
walking in the dark would naturally do for the greater certainty of
following his conductress, while the general part of the symbol of
IMMORTAL LIFE, being turned toward the figure of Pluto, shews that
she
is leading the phantom to his realms.
In the Pamphili gardens at Rome, Perseus in assisting Andromeda to
descend from the rock takes hold of her elbow to steady or support
her
step, and she lays her hand loosely on his arm as in this figure.
Admir.
Roman. Antiq.
The figure of PLUTO can not be mistaken, as is agreed by most of
the
writers who have mentioned this vase; his grisley beard, and his
having
one foot buried in the earth, denotes the infernal monarch. He is
placed
at the lowest part of the group, and resting his chin on his hand,
and
his arm upon his knee, receives the stranger-spirit with
inquisitive
attention; it was before observed that when people think
attentively
they naturally rest their bodies in some easy attitude, that more
animal
power may be employed on the thinking faculty. In this group of
figures
there is great art shewn in giving an idea of a descending plain,
viz.
from earth to Elysium, and yet all the figures are in reality on an
horizontal one. This wonderful deception is produced first by the
descending step of the manes or ghost; secondly, by the arm of the
sitting figure of immortal life being raised up to receive him as
he
descends; and lastly, by Pluto having one foot sunk into the earth.
There is yet another figure which is concerned in conducing the
manes or
ghost to the realms of Pluto, and this is LOVE. He precedes the
descending spirit on expanded wings, lights him with his torch, and
turning back his beautiful countenance beckons him to advance. The
antient God of love was of much higher dignity than the modern
Cupid. He
was the first that came out of the great egg of night, (Hesiod.
Theog.
V. CXX. Bryant's Mythol. Vol. II. p. 348.) and is said to possess
the
keys of the sky, sea, and earth. As he therefore led the way into
this
life, he seems to constitute proper emblem for leading the way to a
future life. See Bacon's works. Vol. I. p. 568. and Vol. III. p.
582.
Quarto edit.
The introduction of love into this part of the mysteries requires a
little further explanation. The Psyche of the Aegyptians was one of
their most favourite emblems, and represented the soul, or a future
life; it was originally no other than the aurelia, or butterfly,
but in
after times was represented by a lovely female child with the
beautiful
wings of that insect. The aurelia, after its first stage as an
eruca or
caterpillar, lies for a season in a manner dead, and is inclosed in
a
sort of coffin, in this state of darkness it remains all the
winter, but
at the return of spring it bursts its bonds and comes out with new
life,
and in the most beautiful attire. The Aegyptians thought this a
very
proper picture of the soul of man, and of the immortality to which
it
aspired. But as this was all owing to divine Love, of which EROS
was an
emblem, we find this person frequently introduced as a concomitant
of
the soul in general or Psyche. (Bryant's Mythol. Vol. II. p. 386.)
EROS,
or divine Love, is for the same reason a proper attendant on the
manes
or soul after death, and much contributes to tell the story, that
is, to
shew that a soul or manes is designed by the descending figure.
From
this figure of Love M. D'Hancarville imagines that Orpheus and
Eurydice
are typified under the figure of the manes and immortal life as
above
described. It may be sufficient to answer, first, that Orpheus is
always
represented with a lyre, of which there are prints of four
different
gems in Spence's Polymetis, and Virgil so describes him, Aen. VI.
cythara fretus. And secondly, that it is absurd to suppose that
Eurydice
was fondling and playing with a serpent that had slain her. Add to
this
that Love seems to have been an inhabitant of the infernal regions,
as
exhibited in the mysteries, for Claudian, who treats more openly of
the
Eleusinian mysteries, when they were held in less veneration,
invokes
the deities to disclose to him their secrets, and amongst other
things
by what torch Love softens Pluto.
Dii, quibus in numerum, &c.
Vos mihi sacrarum penetralia pandite rerum,
Et vestri secreta poli, qua lampade Ditem
Flexit amor.
In this compartment there are two trees, whose branches spread over
the
figures, one of them has smoother leaves like some evergreens, and
might
thence be supposed to have some allusion to immortality, but they
may
perhaps have been designed only as ornaments, or to relieve the
figures,
or because it was in groves, where these mysteries were originally
celebrated. Thus Homer speaks of the woods of Proserpine, and
mentions
many trees in Tartarus, as presenting their fruits to Tantalus;
Virgil
speaks of the pleasant groves of Elysium; and in Spence's Polymetis
there are prints of two antient gems, one of Orpheus charming
Cerberus
with his lyre, and the other of Hercules binding him in a cord,
each of
them standing by a tree. Polymet. p. 284. As however these trees
have
all different foliage so clearly marked by the artist, they may
have had
specific meanings in the exhibitions of the mysteries, which have
not
reached posterity, of this kind seem to have been the tree of
knowledge
of good and evil, and the tree of life, in sacred writ, both which
must
have been emblematic or allegorical. The masks, hanging to the
handles
of the vase, seem to indicate that there is a concealed meaning in
the
figures besides their general appearance. And the priestess at the
bottom, which I come now to describe, seems to shew this concealed
meaning to be of the sacred or Eleusinian kind.
3. The figure on the bottom of the vase is on a larger scale than
the
others, and less finely finished, and less elevated, and as this
bottom
part was afterwards cemented to the upper part, it might be
executed by
another artist for the sake of expedition, but there seems no
reason to
suppose that it was not originally designed for the upper part of
it as
some have conjectured. As the mysteries of Ceres were celebrated by
female priests, for Porphyrius says the antients called the
priestesses
of Ceres, Melissai, or bees, which were emblems of chastity. Div.
Leg.
Vol. I. p. 235. And as, in his Satire against the sex, Juvenal
says,
that few women are worthy to be priestesses of Ceres. Sat. VI. the
figure at the bottom of the vase would seem to represent a
PRIESTESS or
HIEROPHANT, whose office it was to introduce the initiated, and
point
out to them, and explain the exhibitions in the mysteries, and to
exclude the uninitiated, calling out to them, “Far, far retire, ye
profane!” and to guard the secrets of the temple. Thus the
introductory
hymn sung by the hierophant, according to Eusebius, begins, “I will
declare a secret to the initiated, but let the doors be shut
against the
profane.” Div. Leg. Vol. I. p. 177. The priestess or hierophant
appears
in this figure with a close hood, and dressed in linen, which fits
close
about her; except a light cloak, which flutters in the wind. Wool,
as
taken from slaughtered animals, was esteemed profane by the priests
of
Aegypt, who were always dressed in linen. Apuleus, p. 64. Div. Leg.
Vol.
I. p. 318. Thus Eli made for Samuel a linen ephod. Samuel i. 3.
Secrecy was the foundation on which all mysteries rested, when
publicly
known they ceased to be mysteries; hence a discovery of them was
not
only punished with death by the Athenian law; but in other
countries a
disgrace attended the breach of a solemn oath. The priestess in the
figure before us has her finger pointing to her lips as an emblem
of
silence. There is a figure of Harpocrates, who was of Aegyptian
origin,
the same as Orus, with the lotus on his head, and with his finger
pointing to his lips not pressed upon them, in Bryant's Mythol.
Vol. II.
p. 398, and another female figure standing on a lotus, as if just
risen
from the Nile, with her finger in the same attitude, these seem to
have
been representations or emblems of male and female priests of the
secret
mysteries. As these sort of emblems were frequently changed by
artists
for their more elegant exhibition, it is possible the foliage over
the
head of this figure may bear some analogy to the lotus above
mentioned.
This figure of secrecy seems to be here placed, with great
ingenuity, as
a caution to the initiated, who might understand the meaning of the
emblems round the vase, not to divulge it. And this circumstance
seems
to account for there being no written explanation extant, and no
tradition concerning these beautiful figures handed down to us
along
with them.
Another explanation of this figure at the bottom of the vase would
seem
to confirm the idea that the basso relievos round its sides are
representations of a part of the mysteries, I mean that it is the
head
of ATIS. Lucian says that Atis was a young man of Phrygia, of
uncommon
beauty, that he dedicated a temple in Syria to Rhea, or Cybele, and
first taught her mysteries to the Lydians, Phrygians, and
Samothracians,
which mysteries he brought from India. He was afterwards made an
eunuch
by Rhea, and lived like a woman, and assumed a feminine habit, and
in
that garb went over the world teaching her ceremonies and
mysteries.
Dict. par M. Danet, art. Atis. As this figure is covered with
clothes,
while those on the sides of the vase are naked, and has a Phrygian
cap
on the head, and as the form and features are so soft, that it is
difficult to say whether it be a male or female figure, there is
reason
to conclude, 1. that it has reference to some particular person of
some
particular country; 2. that this person is Atis, the first great
hierophant, or teacher of mysteries, to whom M. De la Chausse says
the
figure itself bears a resemblance. Museo. Capitol. Tom. IV. p. 402.
In the Museum Etruscum, Vol. I. plate 96, there is the head of Atis
with
feminine features, clothed with a Phrygian cap, and rising from
very
broad foliage, placed on a kind of term supported by the paw of a
lion.
Goreus in his explanation of the figure says that it is placed on a
lion's foot because that animal was sacred to Cybele, and that it
rises
from very broad leaves because after he became an eunuch he
determined
to dwell in the groves. Thus the foliage, as well as the cap and
feminine features, confirm the idea of this figure at the bottom of
the
vase representing the head of Atis the first great hierophant, and
that
the figures on the sides of the vase are emblems from the antient
mysteries.
I beg leave to add that it does not appear to have been uncommon
amongst
the antients to put allegorical figures on funeral vases. In the
Pamphili palace at Rome there is an elaborate representation of
Life and
of Death, on an antient sarcophagus. In the first Prometheus is
represented making man, and Minerva is placing a butterfly, or the
soul,
upon his head. In the other compartment Love extinguishes his torch
in
the bosom of the dying figure, and is receiving the butterfly, or
Psyche, from him, with a great number of complicated emblematic
figures
grouped in very bad taste. Admir. Roman. Antiq.
Whence sable Coal his massy couch extends,
And stars of gold the sparkling Pyrite blends.
CANTO II. l. 349.
To elucidate the formation of coal-beds I shall here describe a
fountain
of fossil tar, or petroleum, discovered lately near Colebrook Dale
in
Shropshire, the particulars of which were sent me by Dr. Robert
Darwin
of Shrewsbury.
About a mile and a half below the celebrated iron-bridge,
constructed by
the late Mr. DARBY near Colebrook Dale, on the east side of the
river
Severn, as the workmen in October 1786 were making a subterranean
canal
into the mountain, for the more easy acquisition and conveyance of
the
coals which lie under it, they found an oozing of liquid bitumen,
or
petroleum; and as they proceeded further cut through small cavities
of
different sizes from which the bitumen issued. From ten to fifteen
barrels of this fossil tar, each barrel containing thirty-two
gallons,
were at first collected in a day, which has since however gradually
diminished in quantity, so that at present the product is about
seven
barrels in fourteen days.
The mountain, into which this canal enters, consists of siliceous
sand,
in which however a few marine productions, apparently in their
recent
state, have been found, and are now in the possession of Mr.
WILLIAM
REYNOLDS of Ketly Bank. About three hundred yards from the entrance
into
the mountain, and about twenty-eight yards below the surface of it,
the
tar is found oozing from the sand-rock above into the top and sides
of
the canal.
Beneath the level of this canal a shaft has been sunk through a
grey
argillaceous substance, called in this country clunch, which is
said to
be a pretty certain indication of coal; beneath this lies a stratum
of
coal, about two or three inches thick, of an inferior kind,
yielding
little flame in burning, and leaving much ashes; below this is a
rock of
a harder texture; and beneath this are found coals of an excellent
quality; for the purpose of procuring which with greater facility
the
canal, or horizontal aperture, is now making into the mountain.
July,
1788.
Beneath these coals in some places is found salt water, in other
parts
of the adjacent country there are beds of iron-stone, which also
contain
some bitumen in a less fluid state, and which are about on a level
with
the new canal, into which the fossil tar oozes, as above described.
There are many interesting circumstances attending the situation
and
accompaniments of this fountain of fossil tar, tending to develop
the
manner of its production. 1. As the canal passing into the mountain
runs
over the beds of coals, and under the reservoir of petroleum, it
appears
that a natural distillation of this fossil in the bowels of
the earth
must have taken place at some early period of the world, similar to
the
artificial distillation of coal, which has many years been carried
on in
this place on a smaller scale above ground. When this reservoir of
petroleum was cut into, the slowness of its exsudation into the
canal
was not only owing to its viscidity, but to the pressure of the
atmosphere, or to the necessity there was that air should at the
same
time insinuate itself into the small cavities from which the
petroleum
descended. The existence of such a distillation at some antient
time is
confirmed by the thin stratum of coal beneath the canal, (which
covers
the hard rock,) having been deprived of its fossil oil, so as to
burn
without flame, and thus to have become a natural coak, or fossil
charcoal, while the petroleum distilled from it is found in the
cavities
of the rock above it.
There are appearances in other places, which favour this idea of
the
natural distillation of petroleum, thus at Matlock in Derbyshire a
hard
bitumen is found adhering to the spar in the clefts of the
lime-rocks in
the form of round drops about the size of peas; which could perhaps
only
be deposited there in that form by sublimation.
2. The second deduction, which offers itself, is, that these beds
of
coal have been exposed to a considerable degree of heat,
since the
petroleum above could not be separated, as far as we know, by any
other
means, and that the good quality of the coals beneath the hard rock
was
owing to the impermeability of this rock to the bituminous vapour,
and
to its pressure being too great to permit its being removed by the
elasticity of that vapour. Thus from the degree of heat, the degree
of
pressure, and the permeability of the superincumbent strata, many
of the
phenomena attending coal-beds receive an easy explanation, which
much
accords with the ingenious theory of the earth by Dr. Hutton,
Trans. of
Edinb. Vol. I.
In some coal works the fusion of the strata of coal has been so
slight,
that there remains the appearance of ligneus fibres, and the
impression
of leaves, as at Bovey near Exeter, and even seeds of vegetables,
of
which I have had specimens from the collieries near Polesworth in
Warwickshire. In some, where the heat was not very intense and the
incumbent stratum not permeable to vapour, the fossil oil has only
risen
to the upper part of the coal-bed, and has rendered that much more
inflammable than the lower parts of it, as in the collieries near
Beaudesert, the seat of the EARL OF UXBRIDGE in Staffordshire,
where the
upper stratum is a perfect cannel, or candle-coal, and the lower
one of
an inferior quality. Over the coal-beds near Sir H. HARPUR'S house
in
Derbyshire a thin lamina of asphaltum is found in some places near
the
surface of the earth, which would seem to be from a distillation of
petroleum from the coals below, the more fluid part of which had in
process of time exhaled, or been consolidated by its absorption of
air.
In other coal-works the upper part of the stratum is of a worse
kind
than the lower one, as at Alfreton and Denbigh in Derbyshire, owing
to
the supercumbent stratum having permitted the exhalation of a great
part
of the petroleum; whilst at Widdrington in Northumberland there is
first
a seam of coal about six inches thick of no value, which lies under
about four fathom of clay, beneath this is a white freestone, then
a
hard stone, which the workmen there call a whin, then two fathoms
of
clay, then another white stone, and under that a vein of coals
three
feet nine inches thick, of a similar nature to the Newcastle coal.
Phil.
Trans. Abridg. Vol. VI. plate II. p. 192. The similitude between
the
circumstances of this colliery, and of the coal beneath the
fountain of
tar above described, renders it highly probable that this upper
thin
seam of coal has suffered a similar distillation, and that the
inflammable part of it had either been received into the clay above
in
the form of sulphur, which when burnt in the open air would produce
alum; or had been dissipated for want of a receiver, where it could
be
condensed. The former opinion is perhaps in this case more probable
as
in some other coal-beds, of which I have procured accounts, the
surface
of the coal beneath clunch or clay is of an inferior quality, as at
West
Hallum in Nottinghamshire. The clunch probably from hence acquires
its
inflammable part, which on calcination becomes vitriolic acid. I
gathered pieces of clunch converted partially into alum at a
colliery
near Bilston, where the ground was still on fire a few years ago.
The heat, which has thus pervaded the beds of morass, seems to have
been
the effect of the fermentation of their vegetable materials; as new
hay
sometimes takes fire even in such very small masses from the sugar
it
contains, and seems hence not to have been attended with any
expulsion
of lava, like the deeper craters of volcanos situated in beds of
granite.
3. The marine shells found in the loose sand-rock above this
reservoir
of petroleum, and the coal-beds beneath it, together with the
existence
of sea-salt beneath these coals, prove that these coal beds have
been
at the bottom of the sea, during some remote period of time,
and were
afterwards raised into their present situation by subterraneous
expansions of vapour. This doctrine is further supported by the
marks of
violence, which some coal-beds received at the time they were
raised out
of the sea, as in the collieries at Mendip in Somersetshire. In
these
there are seven strata of coals, equitant upon each other, with
beds of
clay and stone intervening; amongst which clay are found shells and
fern
branches. In one part of this hill the strata are disjoined, and a
quantity of heterogeneous substances fill up the chasm which
disjoins
them, on one side of this chasm the seven strata of coal are seen
corresponding in respect to their reciprocal thickness and goodness
with
the seven strata on the other side of the cavity, except that they
have
been elevated several yards higher. Phil. Trans. No. 360. abridg.
Vol.
V. p. 237.
The cracks in the coal-bed near Ticknall in Derbyshire, and in the
sand-
stone rock over it, in both of which specimens of lead-ore and spar
are
found, confirm this opinion of their having been forcibly raised up
by
subterraneous fires. Over the colliery at Brown-hills near
Lichfield,
there is a stratum of gravel on the surface of the ground; which
may be
adduced as another proof to shew that those coals had some time
been
beneath the sea, or the bed of a river. Nevertheless, these
arguments
only apply to the collieries above mentioned, which are few
compared
with those which bear no marks of having been immersed in the sea.
On the other hand the production of coals from morasses, as
described in
note XX. is evinced from the vegetable matters frequently found in
them,
and in the strata over them; as fern-leaves in nodules of iron-ore,
and
from the bog-shells or fresh water muscles sometimes found over
them, of
both which I have what I believe to be specimens; and is further
proved
from some parts of these beds being only in part transformed to
coal;
and the other part still retaining not only the form, but some of
the
properties of wood; specimens of which are not unfrequent in the
cabinets of the curious, procured from Loch Neigh in Ireland, from
Bovey
near Exeter, and other places; and from a famous cavern called the
Temple of the Devil, near the town of Altorf in Franconia, at the
foot
of a mountain covered with pine and savine, in which are found
large
coals resembling trees of ebony; which are so far mineralized as to
be
heavy and compact; and so to effloresce with pyrites in some parts
as to
crumble to pieces; yet from other parts white ashes are produced on
calcination, from which fixed alcali is procured; which
evinces their
vegetable origin. (Dict. Raisonne, art. Charbon.) To these may be
added
another argument from the oil which is distilled from coals, and
which
is analogous to vegetable oil, and does not exist in any bodies
truly
mineral. Keir's Chemical Dictionary, art. Bitumen.
Whence it would appear, that though most collieries with their
attendant
strata of clay, sand-stone, and iron, were formed on the places
where
the vegetables grew, from which they had their origin; yet that
other
collections of vegetable matter were washed down from eminences by
currents of waters into the beds of rivers, or the neighbouring
seas,
and were there accumulated at different periods of time, and
underwent a
great degree of heat from their fermentation, in the same manner as
those beds of morass which had continued on the plains where they
were
produced. And that by this fermentation many of them had been
raised
from the ocean with sand and sea-shells over them; and others from
the
beds of rivers with accumulations of gravel upon them.
4. For the purpose of bringing this history of the products of
morasses
more distinctly to the eye of the reader, I shall here subjoin two
or
three accounts of sinking or boring for coals, out of above twenty
which
I have procured from various places, though the terms are not very
intelligible, being the language of the overseers of coal-works.
1. Whitfield mine near the Pottery in Staffordshire. Soil 1
foot.
brick-clay 3 feet. shale 4. metal which is hard brown and falls in
the
weather 42. coal 3. warrant clay 6. brown gritstone 36. coal 31/2.
warrant
clay 31/2. bass and metal 531/2. hardstone 4. shaly bass 11/2. coal
4.
warrant clay, depth unknown. in all about 55 yards.
2. Coal-mine at Alfreton in Derbyshire. Soil and clay 7
feet.
fragments of stone 9. bind 13. stone 6. bind 34. stone 5. bind 2.
stone
2. bind 10. coal 11/2. bind 11/2. stone 37. bind 7. soft coal 3.
bind 3.
stone 20. bind 16. coal 71/2. in all about 61 yards.
3. A basset coal-mine at Woolarton in Nottinghamshire. Sand
and gravel
6 feet. bind 21. stone 10. smut or effete coal 1. clunch 4. bind
21.
stone 18. bind 18. stone-bind 15. soft coal 2. clunch and bind 21.
coal
7. in all about 48 yards.
4. Coal-mine at West-Hallam in Nottinghamshire. Soil and
clay 7 feet.
bind 48. smut 11/2. clunch 4. bind 3. stone 2. bind 1. stone 1.
bind 3.
stone 1. bind 16. shale 2. bind 12. shale 3. clunch, stone, and a
bed of
cank 54. soft coal 4. clay and dun 1. soft coal 41/2. clunch and
bind 21.
coal 1. broad bind 26. hard coal 6. in all about 74 yards.
As these strata generally lie inclined, I suppose parallel with the
limestone on which they rest, the upper edges of them all come out
to
day, which is termed bassetting; when the whole mass was ignited by
its
fermentation, it is probable that the inflammable part of some
strata
might thus more easily escape than of others in the form of vapour;
as
dews are known to slide between such strata in the production of
springs; which accounts for some coal-beds being so much worse than
others. See note XX.
From this account of the production of coals from morasses it would
appear, that coal-beds are not to be expected beneath masses of
lime-
stone. Nevertheless I have been lately informed by my friend Mr.
Michell
of Thornhill, who I hope will soon favour the public with his
geological
investigations, that the beds of chalk are the uppermost of all the
limestones; and that they rest on the granulated limestone, called
ketton-stone; which I suppose is similar to that which covers the
whole
country from Leadenham to Sleaford, and from Sleaford to Lincoln;
and
that, thirdly, coal-delphs are frequently found beneath these two
uppermost beds of limestone.
Now as the beds of chalk and of granulated limestone may have been
formed by alluviation, on or beneath the shores of the sea, or in
vallies of the land; it would seem, that some coal countries, which
in
the great commotions of the earth had been sunk beneath the water,
were
thus covered with alluvial limestone, as well as others with
alluvial
basaltes, or common gravel-beds. Very extensive plains which now
consist
of alluvial materials, were in the early times covered with water;
which
has since diminished as the solid parts of the earth have
increased. For
the solid parts of the earth consisting chiefly of animal and
vegetable
recrements must have originally been formed or produced from the
water
by animal and vegetable processes; and as the solid parts of the
earth
may be supposed to be thrice as heavy as water, it follows that
thrice
the quantity of water must have vanished compared with the quantity
of
earth thus produced. This may account for many immense beds of
alluvial
materials, as gravel, rounded sand granulated limestone, and chalk,
covering such extensive plains as Lincoln-heath, having become dry
without the supposition of their having been again elevated from
the
ocean. At the same time we acquire the knowledge of one of the uses
or
final causes of the organized world, not indeed very flattering to
our
vanity, that it converts water into earth, forming islands and
continents by its recrements or exuviae.
Climb the rude steeps, the Granite-cliffs surround.
CANTO II. l. 523.
The lowest stratum of the earth which human labour has arrived to,
is
granite; and of this likewise consists the highest mountains of the
world. It is known under variety of names according to some
difference
in its appearance or composition, but is now generally considered
by
philosophers as a species of lava; if it contains quartz, feltspat,
and
mica in distinct crystals, it is called granite; which is found in
Cornwall in rocks; and in loose stones in the gravel near Drayton
in
Shropshire, in the road towards Newcastle. If these parts of the
composition be less distinct, or if only two of them be visible to
the
eye, it is termed porphyry, trap, whinstone, moorstone, slate. And
if it
appears in a regular angular form, it is called basaltes. The
affinity
of these bodies has lately been further well established by Dr.
Beddoes
in the Phil. Trans. Vol. LXXX.
These are all esteemed to have been volcanic productions that have
undergone different degrees of heat; it is well known that in
Papin's
digester water may be made red hot by confinement, and will then
dissolve many bodies which otherwise are little or not at all acted
upon
by it. From hence it may be conceived, that under immense pressure
of
superincumbent materials, and by great heat, these masses of lava
may
have undergone a kind of aqueous solution, without any tendency to
vitrification, and might thence have a power of crystallization,
whence
all the varieties above mentioned from the different proportion of
the
materials, or the different degrees of heat they may have undergone
in
this aqueous solution. And that the uniformity of the mixture of
the
original earths, as of lime, argil, silex, magnesia, and barytes,
which
they contain, was owing to their boiling together a longer or
shorter
time before their elevation into mountains. See note XIX. art. 8.
The seat of volcanos seems to be principally, if not entirely, in
these
strata of granite; as many of them are situated on granite
mountains,
and throw up from time to time sheets of lava which run down over
the
proceeding strata from the same origin; and in this they seem to
differ
from the heat which has separated the clay, coal, and sand in
morasses,
which would appear to have risen from a kind of fermentation, and
thus
to have pervaded the whole mass without any expuition of lava.
[Illustration: Section of the Earth. A sketch of a supposed
Section of
the Earth in respect to the disposition of the Strata over each
other
without regard to their proportions or number. London Published
Dec'r
1st 1791 by J. Johnson St Paul's Church Yard.]
All the lavas from Vesuvius contain one fourth part of iron,
(Kirwan's
Min.) and all the five primitive earths, viz. calcareous,
argillaceous,
siliceous, barytic, and magnesian earths, which are also evidently
produced now daily from the recrements of animal and vegetable
bodies.
What is to be thence concluded? Has the granite stratum in very
antient
times been produced like the present calcareous and siliceous
masses,
according to the ingenious theory of Dr. Hutton, who says new
continents
are now forming at the bottom of the sea to rise in their turn, and
that
thus the terraqueous globe has been, and will be, eternal? Or shall
we
suppose that this internal heated mass of granite, which forms the
nucleus of the earth, was a part of the body of the sun before it
was
separated by an explosion? Or was the sun originally a planet,
inhabited
like ours, and a satellite to some other greater sun, which has
long
been extinguished by diffusion of its light, and around which the
present sun continues to revolve, according to a conjecture of the
celebrated Mr. Herschell, and which conveys to the mind a most
sublime
idea of the progressive and increasing excellence of the works of
the
Creator of all things?
For the more easy comprehension of the facts and conjectures
concerning
the situation and production of the various strata of the earth, I
shall
here subjoin a supposed section of the globe, but without any
attempt to
give the proportions of the parts, or the number of them, but only
their
respective situation over each other, and a geological
recapitulation.
GEOLOGICAL RECAPITULATION.
1. The earth was projected along with the other primary planets
from the
sun, which is supposed to be on fire only on its surface, emitting
light
without much internal heat like a ball of burning camphor.
2. The rotation of the earth round its axis was occasioned by its
greater friction or adhesion to one side of the cavity from which
it was
ejected; and from this rotation it acquired its spheroidical form.
As it
cooled in its ascent from the sun its nucleus became harder; and
its
attendant vapours were condensed, forming the ocean.
3. The masses or mountains of granite, porphery, basalt, and stones
of
similar structure, were a part of the original nucleus of the
earth; or
consist of volcanic productions since formed.
4. On this nucleus of granite and basaltes, thus covered by the
ocean,
were formed the calcareous beds of limestone, marble, chalk, spar,
from
the exuviae of marine animals; with the flints, or chertz, which
accompany them. And were stratified by their having been formed at
different and very distant periods of time.
5. The whole terraqueous globe was burst by central fires; islands
and
continents were raised, consisting of granite or lava in some
parts, and
of limestone in others; and great vallies were sunk, into which the
ocean retired.
6. During these central earthquakes the moon was ejected from the
earth,
causing new tides; and the earth's axis suffered some change in its
inclination, and its rotatory motion was retarded.
7. On some parts of these islands and continents of granite or
limestone
were gradually produced extensive morasses from the recrements of
vegetables and of land animals; and from these morasses, heated by
fermentation, were produced clay, marle, sandstone, coal, iron,
(with
the bases of variety of acids;) all which were stratified by their
having been formed at different, and very distant periods of time.
8. In the elevation of the mountains very numerous and deep
fissures
necessarily were produced. In these fissures many of the metals are
formed partly from descending materials, and partly from ascending
ones
raised in vapour by subterraneous fires. In the fissures of granite
or
porphery quartz is formed; in the fissures of limestone calcareous
spar
is produced.
9. During these first great volcanic fires it is probable the
atmosphere
was either produced, or much increased; a process which is perhaps
now
going on in the moon; Mr. Herschell having discovered a volcanic
crater
three miles broad burning on her disk.
10. The summits of the new mountains were cracked into innumerable
lozenges by the cold dews or snows falling upon them when red hot.
From
these summits, which were then twice as high as at present, cubes
and
lozenges of granite, and basalt, and quartz in some countries, and
of
marble and flints in others, descended gradually into the valleys,
and
were rolled together in the beds of rivers, (which were then so
large as
to occupy the whole valleys, which they now only intersect;) and
produced the great beds of gravel, of which many valleys consist.
11. In several parts of the earth's surface subsequent earthquakes,
from
the fermentation of morasses, have at different periods of time
deranged
the position of the matters above described. Hence the gravel,
which was
before in the beds of rivers, has in some places been raised into
mountains, along with clay and coal strata which were formed from
morasses and washed down from eminences into the beds of rivers or
the
neighbouring seas, and in part raised again with gravel or marine
shells
over them; but this has only obtained in few places compared with
the
general distribution of such materials. Hence there seem to have
existed
two sources of earthquakes, which have occurred at great distance
of
time from each other; one from the granite beds in the central
parts of
the earth, and the other from the morasses on its surface. All the
subsequent earthquakes and volcanos of modern days compared with
these
are of small extent and insignificant effect.
12. Besides the argillaceous sand-stone produced from morasses,
which is
stratified with clay, and coal, and iron, other great beds of
siliceous
sand have been formed in the sea by the combination of an unknown
acid
from morasses, and the calcareous matters of the ocean.
13. The warm waters which are found in many countries, are owing to
steam arising from great depths through the fissures of limestone
or
lava, elevated by subterranean fires, and condensed between the
strata
of the hills over them; and not from any decomposition of pyrites
or
manganese near the surface of the earth.
14. The columns of basaltes have been raised by the congelation or
expansion of granite beds in the act of cooling from their
semi-vitreous
fusion.
Aquatic nymphs! you lead with viewless march
The winged vapour up the aerial arch.
CANTO III. l. 13.
I. The atmosphere will dissolve a certain quantity of moisture as a
chemical menstruum, even when it is much below the freezing point,
as
appears from the diminution of ice suspended in frosty air, but a
much
greater quantity of water is evaporated and suspended in the air by
means of heat, which is perhaps the universal cause of fluidity,
for
water is known to boil with less heat in vacuo, which is a proof
that it
will evaporate faster in vacuo, and that the air therefore rather
hinders than promotes its evaporation in higher degrees of heat.
The
quick evaporation occasioned in vacuo by a small degree of heat is
agreeably seen in what is termed a pulse-glass, which consists of
an
exhausted tube of glass with a bulb at each end of it and with
about two
thirds of the cavity filled with alcohol, in which the spirit is
instantly seen to boil by the heat of the finger-end applied on a
bubble
of steam in the lower bulb, and is condensed again in the upper
bulb by
the least conceivable comparative coldness.
2. Another circumstance evincing that heat is the principal cause
of
evaporation is that at the time of water being converted into
steam, a
great quantity of heat is taken away from the neighbouring bodies.
If a
thermometer be repeatedly dipped in ether, or in rectified spirit
of
wine, and exposed to a blast of air, to expedite the evaporation by
perpetually removing the saturated air from it, the thermometer
will
presently sink below freezing. This warmth, taken from the ambient
bodies at the time of evaporation by the steam, is again given out
when
the steam is condensed into water. Hence the water in a worm-tub
during
distillation so soon becomes hot; and hence the warmth accompanying
the
descent of rain in cold weather.
3. The third circumstance, shewing that heat is the principal cause
of
evaporation, is, that some of the steam becomes again condensed
when any
part of the heat is withdrawn. Thus when warmer south-west winds
replete
with moisture succeed the colder north-east winds all bodies that
are
dense and substantial, as stone walls, brick floors, &c. absorb
some of
the heat from the passing air, and its moisture becomes
precipitated on
them, while the north-east winds become warmer on their arrival in
this
latitude, and are thence disposed to take up more moisture, and are
termed drying winds.
4. Heat seems to be the principal cause of the solution of many
other
bodies, as common salt, or blue vitriol dissolved in water, which
when
exposed to severe cold are precipitated, or carried, to the part of
the
water last frozen; this I observed in a phial filled with a
solution of
blue vitriol which was frozen; the phial was burst, the ice thawed,
and
a blue column of cupreous vitriol was left standing upright on the
bottom of the broken glass, as described in note XIX.
II. Hence water may either be dissolved in air, and may then be
called
an aerial solution of water; or it may be dissolved in the fluid
matter
of heat, according to the theory of M. Lavoisier, and may then be
called
steam. In the former case it is probable there are many other
vapours
which may precipitate it, as marine acid gas, or fluor acid gas. So
alcaline gas and acid gas dissolved in air precipitate each other,
nitrous gas precipitates vital air from its azote, and inflammable
gas
mixed with vital air ignited by an electric spark either produces
or
precipitates the water in both of them. Are there any subtle
exhalations
occasionally diffused in the atmosphere which may thus cause rain?
1. But as water is perhaps many hundred times more soluble in the
fluid
matter of heat than in air, I suppose the eduction of this heat, by
whatever means it is occasioned, is the principal cause of
devaporation.
Thus if a region of air is brought from a warmer climate, as the
S.W.
winds, it becomes cooled by its contact with the earth in this
latitude,
and parts with so much of its moisture as was dissolved in the
quantity
of calorique, or heat, which it now looses, but retains that part
which
was suspended by its attraction to the particles of air, or by
aerial
solution, even in the most severe frosts.
2. A second immediate cause of rain is a stream of N.E. wind
descending
from a superior current of air, and mixing with the warmer S.W.
wind
below; or the reverse of this, viz. a superior current of S.W. wind
mixing with an inferior one of N.E. wind; in both these cases the
whole
heaven becomes instantly clouded, and the moisture contained in the
S.W.
current is precipitated. This cause of devaporation has been
ingeniously
explained by Dr. Hutton in the Transact. of Edinburgh, Vol. I, and
seems
to arise from this circumstance; the particles of air of the N.E.
wind
educe part of the heat from the S.W. wind, and therefore the water
which
was dissolved by that quantity of heat is precipitated; all
the other
part of the water, which was suspended by its attraction to the
particles of air, or dissolved in the remainder of the heat,
continues
unprecipitated.
3. A third method by which a region of air becomes cooled, and in
consequence deposits much of its moisture, is from the mechanical
expansion of air, when part of the pressure is taken off. In this
case
the expanded air becomes capable of receiving or attracting more of
the
matter of heat into its interstices, and the vapour, which was
previously dissolved in this heat, is deposited, as is seen in the
receiver of an air-pump, which becomes dewy, as the air within
becomes
expanded by the eduction of part of it. See note VII. Hence when
the
mercury in the barometer sinks without a change of the wind the air
generally becomes colder. See note VII. on Elementary Heat. And it
is
probably from the varying pressure of the incumbent air that in
summer
days small black clouds are often thus suddenly produced, and again
soon
vanish. See a paper in Philos. Trans. Vol. LXXVIII. intitled
Frigorific
Experiments on the Mechanical Expansion of Air.
4. Another portion of atmospheric water may possibly be held in
solution
by the electric fluid, since in thunder storms a precipitation of
the
water seems to be either the cause or the consequence of the
eduction of
the electricity. But it appears more probable that the water is
condensed into clouds by the eduction of its heat, and that then
the
surplus of electricity prevents their coalescence into larger
drops,
which immediately succeeds the departure of the lightning.
5. The immediate cause why the barometer sinks before rain is,
first,
because a region of warm air, brought to us in the place of the
cold air
which it had displaced, must weigh lighter, both specifically and
absolutely, if the height of the warm atmosphere be supposed to be
equal
to that of the preceeding cold one. And secondly, after the drops
of
rain begin to fall in any column of air, that column becomes
lighter,
the falling drops only adding to the pressure of the air in
proportion
to the resistance which they meet with in passing through that
fluid.
If we could suppose water to be dissolved in air without heat, or
in
very low degrees of heat, I suppose the air would become heavier,
as
happens in many chemical solutions, but if water dissolved in the
matter
of heat, or calorique, be mixed with an aerial solution of water,
there
can be no doubt but an atmosphere consisting of such a mixture must
become lighter in proportion to the quantity of calorique. On the
same
circumstance depends the visible vapour produced from the breath of
animals in cold weather, or from a boiling kettle; the particles of
cold
air, with which it is mixed, steal a part of its heat, and become
themselves raised in temperature, whence part of the water is
precipitated in visible vapour, which, if in great quantity sinks
to the
ground; if in small quantity, and the surrounding air is not
previously
saturated, it spreads itself till it becomes again dissolved.
Your lucid bands condense with fingers chill
The blue mist hovering round the gelid hill.
CANTO III. l. 19.
The surface of the earth consists of strata many of which were
formed
originally beneath the sea, the mountains were afterwards forced up
by
subterraneous fires, as appears from the fissures in the rocks of
which
they consist, the quantity of volcanic productions all over the
world,
and the numerous remains of craters of volcanos in mountainous
countries. Hence the strata which compose the sides of mountains
lie
slanting downwards, and one or two or more of the external strata
not
reaching to the summit when the mountain was raised up, the second
or
third stratum or a more inferior one is there exposed to day; this
may
be well represented by forceably thrusting a blunt instrument
through
several sheets of paper, a bur will stand up with the lowermost
sheet
standing highest in the center of it. On this uppermost stratum,
which
is colder as it is more elevated, the dews are condensed in large
quantities; and sliding down pass under the first or second or
third
stratum which compose the sides of the hill; and either form a
morass
below, or a weeping rock, by oozing out in numerous places, or many
of
these less currents meeting together burst out in a more copious
rill.
The summits of mountains are much colder than the plains in their
vicinity, owing to several causes; 1. Their being in a manner
insulated
or cut off from the common heat of the earth, which is always of 48
degrees, and perpetually counteracts the effects of external cold
beneath that degree. 2. From their surfaces being larger in
proportion
to their solid contents, and hence their heat more expeditiously
carried
away by the ever-moving atmosphere. 3. The increasing rarity of the
air
as the mountain rises. All those bodies which conduct electricity
well
or ill, conduct the matter of heat likewise well or ill. See note
VII.
Atmospheric air is a bad conductor of electricity and thence
confines it
on the body where it is accumulated, but when it is made very rare,
as
in the exhausted receiver, the electric aura passes away
immediately to
any distance. The same circumstance probably happens in respect to
heat,
which is thus kept by the denser air on the plains from escaping,
but is
dissipated on the hills where the air is thinner. 4. As the
currents of
air rise up the sides of mountains they become mechanically
rarefied,
the pressure of the incumbent column lessening as they ascend.
Hence the
expanding air absorbs heat from the mountain as it ascends, as
explained
in note VII. 5. There is another, and perhaps more powerful cause,
I
suspect, which may occasion the great cold on mountains, and in the
higher parts of the atmosphere, and which has not yet been attended
to;
I mean that the fluid matter of heat may probably gravitate round
the
earth, and form an atmosphere on its surface, mixed with the aerial
atmosphere, which may diminish or become rarer, as it recedes from
the
earth's surface, in a greater proportion than the air diminishes.
6. The great condensation of moisture on the summits of hills has
another cause, which is the dashing of moving clouds against them,
in
misty days this is often seen to have great effect on plains, where
an
eminent tree by obstructing the mist as it moves along shall have a
much
greater quantity of moisture drop from its leaves than falls at the
same
time on the ground in its vicinity. Mr. White, in his History of
Selborne gives an account of a large tree so situated, from which a
stream flowed during a moving mist so as to fill the cart-ruts in a
lane
otherwise not very moist, and ingeniously adds, that trees planted
about
ponds of stagnant water contribute much by these means to supply
the
reservoir. The spherules which constitute a mist or cloud are kept
from
uniting by so small a power that a little agitation against the
leaves
of a tree, or the greater attraction of a flat moist surface,
condenses
or precipitates them.
If a leaf has its surface moistened and particles of water separate
from
each other as in a mist be brought near the moistened surface of a
leaf,
each particle will be attracted more by that plain surface of water
on
the leaf than it can be by the surrounding particles of the mist,
because globules only attract each other in one point, whereas a
plain
attracts a globule by a greater extent of its surface.
The common cold springs are thus formed on elevated grounds by the
condensed vapours, and hence are stronger when the nights are cold
after
hot days in spring, than even in the wet days of winter. For the
warm
atmosphere during the day has dissolved much more water than it can
support in solution during the cold of the night, which is thus
deposited in large quantities on the hills, and yet so gradually as
to
soak in between the strata of them, rather than to slide off over
their
surfaces like showers of rain. The common heat of the internal
parts of
the earth is ascertained by springs which arise from strata of
earth too
deep to be affected by the heat of summer or the frosts of winter.
Those
in this country are of 48 degrees of heat, those about Philidelphia
were
said by Dr. Franklin to be 52; whether this variation is to be
accounted
for by the difference of the sun's heat on that country, according
to
the ingenious theory of Mr. Kirwan, or to the vicinity of
subterranean
fires is not yet, I think, decided. There are however subterraneous
streams of water not exactly produced in this manner, as streams
issuing
from fissures in the earth, communicating with the craters of old
volcanoes; in the Peak of Derbyshire are many hollows, called
swallows,
where the land floods sink into the earth, and come out at some
miles
distant, as at Ilam near Ashborne. See note on Fica, Vol. II.
Other streams of cold water arise from beneath the snow on the Alps
and
Andes, and other high mountains, which is perpetualy thawing at its
under surface by the common heat of the earth, and gives rise to
large
rivers. For the origin of warm springs see note on Fucus, Vol. II.
You round Echinus ray his arrowy mail,
Give the keel'd Nautilus his oar and sail.
Firm to his rock with silver cords suspend
The anchored Pinna, and his Cancer-friend.
CANTO III. l. 67.
The armour of the Echinus, or Sea-hedge Hog, consists generally of
moveable spines; (Linnei System. Nat. Vol. I. p. 1102.) and
in that
respect resembles the armour of the land animal of the same name.
The
irregular protuberances on other sea-shells, as on some species of
the
Purpura, and Murex, serve them as a fortification against the
attacks of
their enemies.
It is said that this animal foresees tempestuous weather, and
sinking to
the bottom of the sea adheres firmly to sea-plants, or other bodies
by
means of a substance which resembles the horns of snails. Above
twelve
hundred of these fillets have been counted by which this animal
fixes
itself; and when afloat, it contracts these fillets between the
bases of
its points, the number of which often amounts to two thousand. Dict
raisonne. art. Oursin. de mer.
There is a kind of Nautilus, called by Linneus, Argonauta, whose
shell
has but one cell; of this animal Pliny affirms, that having
exonerated
its shell by throwing out the water, it swims upon the surface,
extending a web of wonderful tenuity, and bending back two of its
arms
and rowing with the rest, makes a sail, and at length receiving the
water dives again. Plin. IX. 29. Linneus adds to his description of
this
animal, that like the Crab Diogenes or Bernhard, it occupies a
house
not its own, as it is not connected to its shell, and is therefore
foreign to it; who could have given credit to this if it had not
been
attested by so many who have with their own eyes seen this argonaut
in
the act of sailing? Syst. Nat p. 1161.
The Nautilus, properly so named by Linneus, has a shell consisting
of
many chambers, of which cups are made in the East with beautiful
painting and carving on the mother-pearl. The animal is said to
inhabit
only the uppermost or open chamber, which is larger than the rest;
and
that the rest remain empty except that the pipe, or siphunculus,
which
communicates from one to the other of them is filled with an
appendage
of the animal like a gut or string. Mr. Hook in his Philos. Exper.
p.
306, imagines this to be a dilatable or compressible tube, like the
air-
bladders of fish, and that by contracting or permitting it to
expand, it
renders its shell boyant or the contrary. See Note on Ulva, Vol.
II.
The Pinna, or Sea-wing, is contained in a two-valve shell, weighing
sometimes fifteen pounds, and emits a beard of fine long glossy
silk-
like fibres, by which it is suspended to the rocks twenty or thirty
feet
beneath the surface of the sea. In this situation it is so
successfully
attacked by the eight-footed Polypus, that the species perhaps
could not
exist but for the exertions of the Cancer Pinnotheris, who lives in
the
same shell as a guard and companion. Amoen. Academ. Vol. II. p. 48.
Lin.
Syst. Nat. Vol. I. p. 1159, and p. 1040.
The Pinnotheris, or Pinnophylax, is a small crab naked like Bernard
the
Hermit, but is furnished with good eyes, and lives in the same
shell
with the Pinna; when they want food the Pinna opens its shell, and
sends
its faithful ally to forage; but if the Cancer sees the Polypus, he
returns suddenly to the arms of his blind hostess, who by closing
the
shell avoids the fury of her enemy; otherwise, when it has procured
a
booty, it brings it to the opening of the shell, where it is
admitted,
and they divide the prey. This was observed by Haslequist in his
voyage
to Palestine.
The Byssus of the antients, according to Aristotle, was the beard
of the
Pinna above mentioned, but seems to have been used by other writers
indiscriminately for any spun material, which was esteemed finer or
more
valuable than wool. Reaumur says the threads of this Byssus are not
less
fine or less beautiful than the silk, as it is spun by the
silk-worm;
the Pinna on the coasts of Italy and Provence (where it is fished
up by
iron-hooks fixed on long poles) is called the silk-worm of the sea.
The
stockings and gloves manufactured from it, are of exquisite
fineness,
but too warm for common wear, and are thence esteemed useful in
rhumatism and gout. Dict. raisonne art. Pinne-marine. The warmth of
the
Byssus, like that of silk, is probably owing to their being bad
conductors of heat, as well as of electricity. When these fibres
are
broken by violence, this animal as well as the muscle has the power
to
reproduce them like the common spiders, as was observed by M.
Adanson.
As raw silk, and raw cobwebs, when swallowed, are liable to produce
great sickness (as I am informed) it is probable the part of
muscles,
which sometimes disagrees with the people who eat them, may be this
silky web, by which they attach themselves to stones. The large
kind of
Pinna contains some mother-pearl of a reddish tinge, according to
M.
d'Argenville. The substance sold under the name of Indian weed, and
used
at the bottom of fish-lines, is probably a production of this kind;
which however is scarcely to be distinguished by the eye from the
tendons of a rat's tail, after they have been separated by
putrefaction
in water, and well cleaned and rubbed; a production, which I was
once
shewn as a great curiosity; it had the uppermost bone of the tail
adhering to it, and was said to have been used as an ornament in a
lady's hair.
With worm-like hard his toothless lips array,
And teach the unweildy Sturgeon to betray.
CANTO III. l. 71.
The Sturgeon, Acipenser, Strurio. Lin. Syst. Nat. Vol. I. p.
403. is a
fish of great curiosity as well as of great importance; his mouth
is
placed under the head, without teeth, like the opening of a purse,
which
he has the power to push suddenly out or retract. Before this mouth
under the beak or nose hang four tendrils some inches long, and
which so
resemble earth-worms that at first sight they may be mistaken for
them.
This clumsy toothless fish is supposed by this contrivance to keep
himself in good condition, the solidity of his flesh evidently
shewing
him to be a fish of prey. He is said to hide his large body amongst
the
weeds near the sea-coast, or at the mouths of large rivers, only
exposing his cirrhi or tendrils, which small fish or sea-insects
mistaking for real worms approach for plunder, and are sucked into
the
jaws of their enemy. He has been supposed by some to root into the
soil
at the bottom of the sea or rivers; but the cirrhi, or tendrills
abovementioned, which hang from his snout over his mouth, must
themselves be very inconvenient for this purpose, and as it has no
jaws
it evidently lives by suction, and during its residence in the sea
a
quantity of sea-insects are found in its stomach.
The flesh was so valued in the time of the Emperor Severus, that it
was
brought to table by servants with coronets on their heads, and
preceded
by music, which might give rise to its being in our country
presented by
the Lord Mayor to the King. At present it is caught in the Danube,
and
the Walga, the Don, and other large rivers for various purposes.
The
skin makes the best covering for carriages; isinglass is prepared
from
parts of the skin; cavear from the spawn; and the flesh is pickled
or
salted, and sent all over Europe.
Who with fine films, suspended o'er the deep,
Of Oil effusive lull the waves to sleep.
CANTO III. l. 87.
There is reason to believe that when oil is poured upon water, the
two
surfaces do not touch each other, but that the oil is suspended
over the
water by their mutual repulsion. This seems to be rendered probable
by
the following experiment: if one drop of oil be droped on a bason
of
water, it will immediately diffuse itself over the whole, for there
being no friction between the two surfaces, there is nothing to
prevent
its spreading itself by the gravity of the upper part of it, except
its
own tenacity, into a pellicle of the greatest tenuity. But if a
second
drop of oil be put upon the former, it does not spread itself, but
remains in the form of a drop, as the other already occupied the
whole
surface of the bason, and there is friction in oil passing over
oil,
though none in oil passing over water.
Hence when oil is diffused on the surface of water gentle breezes
have
no influence in raising waves upon it; for a small quantity of oil
will
cover a very great surface of water, (I suppose a spoonful will
diffuse
itself over some acres) and the wind blowing upon this carries it
gradually forwards; and there being no friction between the two
surfaces
the water is not affected. On which account oil has no effect in
stilling the agitation of the water after the wind ceases, as was
found
by the experiments of Dr. Franklin.
This circumstance lately brought into notice by Dr. Franklin had
been
mentioned by Pliny, and is said to be in use by the divers for
pearls,
who in windy weather take down with them a little oil in their
mouths,
which they occasionally give out when the inequality of the
supernatant
waves prevents them from seeing sufficiently distinctly for their
purpose.
The wonderful tenuity with which oil can be spread upon water is
evinced
by a few drops projected from a bridge, where the eye is properly
placed
over it, passing through all the prismatic colours as it diffuses
itself. And also from another curious experiment of Dr. Franklin's:
he
cut a piece of cork to about the size of a letter-wafer, leaving a
point
standing off like a tangent at one edge of the circle. This piece
of
cork was then dipped in oil and thrown into a large pond of water,
and
as the oil flowed off at the point, the cork-wafer continued to
revolve
in a contrary direction for several minutes. The oil flowing off
all
that time at the pointed tangent in coloured streams. In a small
pond of
water this experiment does not so well succeed, as the circulation
of
the cork stops as soon as the water becomes covered with the
pellicle of
oil. See Additional Note, No. XIII. and Note on Fucus, Vol. II.
The ease with which oil and water slide over each other is
agreeably
seen if a phial be about half filled with equal parts of oil and
water,
and made to oscillate suspended by a string, the upper surface of
the
oil and the lower one of the water will always keep smooth; but the
agitation of the surfaces where the oil and water meet, is curious;
for
their specific gravities being not very different, and their
friction on
each other nothing, the highest side of the water, as the phial
descends
in its oscillation, having acquired a greater momentum than the
lowest
side (from its having descended further) would rise the highest on
the
ascending side of the oscillation, and thence pushes the then
uppermost
part of the water amongst the oil.
Meet fell Teredo, as he mines the keel
With beaked head, and break his lips of steel.
CANTO III. l. 91.
The Teredo, or ship-worm, has two calcareous jaws, hemispherical,
flat
before, and angular behind. The shell is taper, winding,
penetrating
ships and submarine wood, and was brought from India into Europe,
Linnei
System. Nat. p. 1267. The Tarieres, or sea-worms, attack and erode
ships
with such fury, and in such numbers, as often greatly to endanger
them.
It is said that our vessels have not known this new enemy above
fifty
years, that they were brought from the sea about the Antilles to
our
parts of the ocean, where they have increased prodigiously. They
bore
their passage in the direction of the fibres of the wood, which is
their
nourishment, and cannot return or pass obliquely, and thence when
they
come to a knot in the wood, or when two of them meet together with
their
stony mouths, they perish for want of food.
In the years 1731 and 1732 the United Provinces were under a
dreadful
alarm concerning these insects, which had made great depredation on
the
piles which support the banks of Zeland, but it was happily
discovered a
few years afterwards that these insects had totally abandoned that
island, (Dict Raisonne, art, Vers Rongeurs,) which might have been
occasioned by their not being able to live in that latitude when
the
winter was rather severer than usual.
Turn the broad helm, the fluttering canvas urge
From Maelstrom's fierce innavigable surge.
CANTO III. l. 93.
On the coast of Norway there is an extensive vortex, or eddy, which
lies
between the islands of Moskoe and Moskenas, and is called
Moskoestrom,
or Maelstrom; it occupies some leagues in circumference, and is
said to
be very dangerous and often destructive to vessels navigating these
seas. It is not easy to understand the existence of a constant
descending stream without supposing it must pass through a
subterranean
cavity to some other part of the earth or ocean which may lie
beneath
its level; as the Mediterranean seems to lie beneath the level of
the
Atlantic ocean, which therefore constantly flows into it through
the
Straits; and the waters of the Gulph of Mexico lie much above the
level
of the sea about the Floridas and further northward, which gives
rise to
the Gulph-stream, as described in note on Cassia in Vol. II.
The Maelstrom is said to be still twice in about twenty-four hours
when
the tide is up, and most violent at the opposite times of the day.
This
is not difficult to account for, since when so much water is
brought
over the subterraneous passage, if such exists, as compleatly to
fill it
and stand many feet above it, less disturbance must appear on the
surface. The Maelstrom is described in the Memoires of the Swedish
Academy of Sciences, and Pontoppiden's Hist. of Norway, and in
Universal
Museum for 1763, p. 131.
The reason why eddies of water become hollow in the middle is
because
the water immediately over the centre of the well, or cavity, falls
faster, having less friction to oppose its descent, than the water
over
the circumference or edges of the well. The circular motion or
gyration
of eddies depends on the obliquity of the course of the stream, or
to
the friction or opposition to it being greater on one side of the
well
than the other; I have observed in water passing through a hole in
the
bottom of a trough, which was always kept full, the gyration of the
stream might be turned either way by increasing the opposition of
one
side of the eddy with ones finger, or by turning the spout, through
which the water was introduced, a little more obliquely to the hole
on
one side or on the other. Lighter bodies are liable to be retained
long
in eddies of water, while those rather heavier than water are soon
thrown out beyond the circumference by their acquired momentum
becoming
greater than that of the water. Thus if equal portions of oil and
water
be put into a phial, and by means of a string be whirled in a
circle
round the hand, the water will always keep at the greater distance
from
the centre, whence in the eddies formed in rivers during a flood a
person who endeavours to keep above water or to swim is liable to
be
detained in them, but on suffering himself to sink or dive he is
said
readily to escape. This circulation of water in descending through
a
hole in a vessel Dr. Franklin has ingeniously applied to the
explanation
of hurricanes or eddies of air.
While round dark crags imprison'd waters bend
Through rifted ice, in ivory veins descend.
CANTO III. l. 113.
The common heat of the interior parts of the earth being always 48
degrees, both in winter and summer, the snow which lies in contact
with
it is always in a thawing state; Hence in ice-houses the external
parts
of the collection of ice is perpetually thawing and thus preserves
the
internal part of it; so that it is necessary to lay up many tons
for the
preservation of one ton. Hence in Italy considerable rivers have
their
source from beneath the eternal glaciers, or mountains of snow and
ice.
In our country when the air in the course of a frost continues a
day or
two at very near 32 degrees, the common heat of the earth thaws the
ice
on its surface, while the thermometer remains at the freezing
point.
This circumstance is often observable in the rimy mornings of
spring;
the thermometer shall continue at the freezing point, yet all the
rime
will vanish, except that which happens to lie on a bridge, a board,
or
on a cake of cow-dung, which being thus as it were insulated or cut
off
from so free a communication with the common heat of the earth by
means
of the air under the bridge, or wood, or dung, which are bad
conductors
of heat, continues some time longer unthawed. Hence when the ground
is
covered thick with snow, though the frost continues, and the sun
does
not shine, yet the snow is observed to decrease very sensibly. For
the
common heat of the earth melts the under surface of it, and the
upper
one evaporates by its solution in the air. The great evaporation of
ice
was observed by Mr. Boyle, which experiment I repeated some time
ago.
Having suspended a piece of ice by a wire and weighed it with care
without touching it with my hand, I hung it out the whole of a
clear
frosty night, and found in the morning it had lost nearly a fifth
of its
weight. Mr. N. Wallerius has since observed that ice at the time of
its
congelation evaporates faster than water in its fluid form; which
may be
accounted for from the heat given out at the instant of freezing;
(Saussure's Essais sur Hygromet. p. 249.) but this effect is only
momentary.
Thus the vegetables that are covered with snow are seldom injured;
since, as they lie between the thawing snow, which has 32 degrees
of
heat, and the covered earth which has 48, they are preserved in a
degree
of heat between these; viz. in 40 degrees of heat. Whence the moss
on
which the rein-deer feed in the northern latitudes vegetates
beneath the
snow; (See note on Muschus, Vol. II.) and hence many Lapland and
Alpine
plants perished through cold in the botanic garden at Upsal, for in
their native situations, though the cold is much more intense, yet
at
its very commencement they are covered deep with snow, which
remains
till late in the spring. For this fact see Amaenit. Academ. Vol. I.
No.
48. In our climate such plants do well covered with dried fern,
under
which they will grow, and even flower, till the severe vernal
frosts
cease. For the increase of glaciers see Note on Canto I. l. 529.
While southern gales o'er western oceans roll,
And Eurus steals his ice-winds from the pole.
CANTO IV. l. 15.
The theory of the winds is yet very imperfect, in part perhaps
owing to
the want of observations sufficiently numerous of the exact times
and
places where they begin and cease to blow, but chiefly to our yet
imperfect knowledge of the means by which great regions of air are
either suddenly produced or suddenly destroyed.
The air is perpetually subject to increase or diminution from its
combination with other bodies, or its evolution from them. The
vital
part of the air, called oxygene, is continually produced in this
climate
from the perspiration of vegetables in the sunshine, and probably
from
the action of light on clouds or on water in the tropical climates,
where the sun has greater power, and may exert some yet unknown
laws of
luminous combination. Another part of the atmosphere, which is
called
azote, is perpetually set at liberty from animal and vegetable
bodies by
putrefaction or combustion, from many springs of water, from
volatile
alcali, and probably from fixed alcali, of which there is an
exhaustless
source in the water of the ocean. Both these component parts of the
air
are perpetually again diminished by their contact with the soil,
which
covers the surface of the earth, producing nitre. The oxygene is
diminished in the production of all acids, of which the carbonic
and
muriatic exist in great abundance. The azote is diminished in the
growth
of animal bodies, of which it constitutes an important part, and in
its
combinations with many other natural productions.
They are both probably diminished in immense quantities by uniting
with
the inflammable air, which arises from the mud of rivers and lakes
at
some seasons, when the atmosphere is light: the oxygene of the air
producing water, and the azote producing volatile alcali by their
combinations with this inflammable air. At other seasons of the
year
these principles may again change their combinations, and the
atmospheric air be reproduced.
Mr. Lavoisier found that one pound of charcoal in burning consumed
two
pounds nine ounces of vital air, or oxygene. The consumption of
vital
air in the process of making red lead may readily be reduced to
calculation; a small barrel contains about twelve hundred weight of
this
commodity, 1200 pounds of lead by calcination absorb about 144
pounds of
vital air; now as a cubic foot of water weighs 1000 averdupois
ounces,
and as vital air is above 800 times lighter than water, it follows
that
every barrel of red lead contains nearly 2000 cubic feet of vital
air.
If this can be performed in miniature in a small oven, what may not
be
done in the immense elaboratories of nature!
These great elaboratories of nature include almost all her fossil
as
well as her animal and vegetable productions. Dr. Priestley
obtained air
of greater or less purity, both vital and azotic, from almost all
the
fossil substances he subjected to experiment. Four ounce-weight of
lava
from Iceland heated in an earthen retort yielded twenty
ounce-measures
of air.
4 ounce-weight of lava gave 20 ounce measures of air.
7 ............... basaltes .... 104 ......................
2 ............... toadstone .... 40 ......................
11/2 ............... granite .... 20 ......................
1 ............... elvain .... 30 ......................
7 ............... gypsum .... 230 ......................
4 ............... blue slate .... 230 ......................
4 ............... clay .... 20 ......................
4 ............... limestone-spar .... 830 ......................
5 ............... limestone .... 1160 ......................
3 ............... chalk .... 630 ......................
31/2 ............... white iron-ore .... 560
......................
4 ............... dark iron-ore .... 410 ......................
1/2 ............... molybdena .... 25 ......................
1/2 ............... stream tin .... 20 ......................
2 ............... steatites .... 40 ......................
2 ............... barytes .... 26 ......................
2 ............... black wad .... 80 ......................
4 ............... sand stone .... 75 ......................
3 ............... coal .... 700 ......................
In this account the fixed air was previously extracted from the
limestones by acids, and the heat applied was much less than was
necessary to extract all the air from the bodies employed. Add to
this
the known quantities of air which are combined with the calciform
ores,
as the ochres of iron, manganese, calamy, grey ore of lead, and
some
idea may be formed of the great production of air in volcanic
eruptions,
as mentioned in note on Chunda, Vol. II. and of the perpetual
absorptions and evolutions of whole oceans of air from every part
of the
earth.
But there would seem to be an officina aeris, a shop where air is
both
manufactured and destroyed in the greatest abundance within the
polar
circles, as will hereafter be spoken of. Can this be effected by
some
yet unknown law of the congelation of aqueous or saline fluids,
which
may set at liberty their combined heat, and convert a part both of
the
acid and alcali of sea-water into their component airs? Or on the
contrary can the electricity of the northern lights convert
inflammable
air and oxygene into water, whilst the great degree of cold at the
poles
unites the azote with some other base? Another officina aeris, or
manufacture of air, would seem to exist within the tropics or at
the
line, though in a much less quantity than at the poles, owing
perhaps to
the action of the sun's light on the moisture suspended in the air,
as
will also be spoken of hereafter; but in all other parts of the
earth
these absorptions and evolutions of air in a greater or less degree
are
perpetually going on in inconceivable abundance; increased
probably, and
diminished at different seasons of the year by the approach or
retrocession of the sun's light; future discoveries must elucidate
this
part of the subject. To this should be added that as heat and
electricity, and perhaps magnetism, are known to displace air, that
it
is not impossible but that the increased or diminished quantities
of
these fluids diffused in the atmosphere may increase its weight a
well
as its bulk; since their specific attractions or affinities to
matter
are very strong, they probably also possess general gravitation to
the
earth; a subject which wants further investigation. See Note XXVI.
SOUTH-WEST WINDS.
The velocity of the surface of the earth in moving round its axis
diminishes from the equator to the poles. Whence if a region of air
in
this country should be suddenly removed a few degrees towards the
north
it must constitute a western wind, because from the velocity it had
previously acquired in this climate by its friction with the earth
it
would for a time move quicker than the surface of the country it
was
removed to; the contrary must ensue when a region of air is
transported
from this country a few degrees southward, because the velocity it
had
acquired in this climate would be less than that of the earth's
surface
where it was removed to, whence it would appear to constitute a
wind
from the east, while in reality the eminent parts of the earth
would be
carried against the too slow air. But if this transportation of air
from
south to north be performed gradually, the motion of the wind will
blow
in the diagonal between south and west. And on the contrary if a
region
of air be gradually removed from north to south it would also blow
diagonally between the north and east, from whence we may safely
conclude that all our winds in this country which blow from the
north or
east, or any point between them, consist of regions of air brought
from
the north; and that all our winds blowing from the south or west,
or
from any point between them, are regions of air brought from the
south.
It frequently happens during the vernal months that after a
north-east
wind has passed over us for several weeks, during which time the
barometer has flood at above 301/2 inches, it becomes suddenly
succeeded
by a south-west wind, which also continues several weeks, and the
barometer sinks to nearly 281/2 inches. Now as two inches of the
mercury
in the barometer balance one-fifteenth part of the whole
atmosphere, an
important question here presents itself, what is become of all
this
air.
1. This great quantity of air can not be carried in a superior
current
towards the line, while the inferior current slows towards the
poles,
because then it would equally affect the barometer, which should
not
therefore subside from 301/2 inches to 281/2 for six weeks
together.
2. It cannot be owing to the air having lost all the moisture which
was
previously dissolved in it, because these warm south-west winds are
replete with moisture, and the cold north-east winds, which weigh
up the
mercury in the barometer to 31 inches, consist of dry air.
3. It can not be carried over the polar regions and be accumulated
on
the meridian, opposite to us in its passage towards the line, as
such an
accumulation would equal one-fifteenth of the whole atmosphere, and
can
not be supposed to remain in that situation for six weeks together.
4. It can not depend on the existence of tides in the atmosphere,
since
it must then correspond to lunar periods. Nor to accumulations of
air
from the specific levity of the upper regions of the atmosphere,
since
its degree of fluidity must correspond with its tenuity, and
consequently such great mountains of air can not be supposed to
exist
for so many weeks together as the south west winds sometimes
continue.
5. It remains therefore that there must be at this time a great and
sudden absorption of air in the polar circle by some unknown
operation
of nature, and that the south wind runs in to supply the
deficiency. Now
as this south wind consists of air brought from a part of the
earth's
surface which moves faster than it does in this climate it must
have at
the same time a direction from the west by retaining part of the
velocity it had previously acquired. These south-west winds coming
from
a warmer country, and becoming colder by their contact with the
earth of
this climate, and by their expansion, (so great a part of the
superincumbent atmosphere having vanished,) precipitate their
moisture;
and as they continue for several weeks to be absorbed in the polar
circle would seem to receive a perpetual supply from the tropical
regions, especially over the line, as will hereafter be spoken of.
It may sometimes happen that a north-east wind having passed over
us may
be bent down and driven back before it has acquired any heat from
the
climate, and may thus for a few hours or a day have a south-west
direction, and from its descending from a higher region of the
atmosphere may possess a greater degree of cold than an inferior
north
east current of air.
The extreme cold of Jan. 13, 1709, at Paris came on with a gentle
south
wind, and was diminished when the wind changed to the north, which
is
accounted for by Mr. Homberg from a reflux of air which had been
flowing
for some time from the north. Chemical Essays by R. Watson, Vol. V.
p.
182.
It may happen that a north-east current may for a day or two pass
over
us and produce incessant rain by mixing with the inferior
south-west
current; but this as well as the former is of short duration, as
its
friction will soon carry the inferior current along with it, and
dry or
frosty weather will then succeed.
NORTH-EAST WINDS.
The north-east winds of this country consist of regions of air from
the
north, travelling sometimes at the rate of about a mile in two
minutes
during the vernal months for several weeks together from the polar
regions toward the south, the mercury in the barometer standing
above
30. These winds consist of air greatly cooled by the evaporation of
the
ice and snow over which it passes, and as they become warmer by
their
contact with the earth of this climate are capable of dissolving
more
moisture as they pass along, and are thence attended with frosts in
winter and with dry hot weather in summer.
1. This great quantity of air can not be supplied by superior
currents
passing in a contrary direction from south to north, because such
currents must as they arise into the atmosphere a mile or two high
become exposed to so great cold as to occasion them to deposit
their
moisture, which would fall through the inferior current upon the
earth
in some part of their passage.
2. The whole atmosphere must have increased in quantity, because it
appears by the barometer that there exists one-fifteenth part more
air
over us for many weeks together, which could not be thus
accumulated by
difference of temperature in respect to heat, or by any aerostatic
laws
at present known, or by any lunar influence.
From whence it would appear that immense masses of air were set at
liberty from their combinations with solid bodies, along with a
sufficient quantity of combined heat, within the polar circle, or
in
some region to the north of us; and that they thus perpetually
increase
the quantity of the atmosphere; and that this is again at certain
times
re-absorbed, or enters into new combinations at the line or
tropical
regions. By which wonderful contrivance the atmosphere is
perpetually
renewed and rendered fit for the support of animal and vegetable
life.
SOUTH-EAST WINDS.
The south-east winds of this country consist of air from the north
which
had passed by us, or over us, and before it had obtained the
velocity of
the earth's surface in this climate had been driven back, owing to
a
deficiency of air now commencing at the polar regions. Hence these
are
generally dry or freezing winds, and if they succeed north-east
winds
should prognosticate a change of wind from north-east to
south-west; the
barometer is generally about 30. They are sometimes attended with
cloudy
weather, or rain, owing to their having acquired an increased
degree of
warmth and moisture before they became retrograde; or to their
being
mixed with air from the south.
2. Sometimes these south-east winds consist of a vertical eddy of
north-
east air, without any mixture of south-west air; in that case the
barometer continues above 30, and the weather is dry or frosty for
four
or five days together.
It should here be observed, that air being an elastic fluid must be
more
liable to eddies than water, and that these eddies must extend into
cylinders or vortexes of greater diameter, and that if a vertical
eddy
of north-east air be of small diameter or has passed but a little
way to
the south of us before its return, it will not have gained the
velocity
of the earth's surface to the south of us, and will in consequence
become a south-east wind.—But if the vertical eddy be of large
diameter, or has passed much to the south of us, it will have
acquired
velocity from its friction with the earth's surface to the south of
us,
and will in consequence on its return become a south-west wind,
producing great cold.
NORTH-WEST WINDS.
There seem to be three sources of the north-west winds of this
hemisphere of the earth. 1. When a portion of southern air, which
was
passing over us, is driven back by accumulation of new air in the
polar
regions. In this case I suppose they are generally moist or rainy
winds,
with the barometer under 30, and if the wind had previously been in
the
south-west, it would seem to prognosticate a change to the
north-east.
2. If a current of north wind is passing over us but a few miles
high,
without any easterly direction; and is bent down upon us, it must
immediately possess a westerly direction, because it will now move
faster than the surface of the earth where it arrives; and thus
becomes
changed from a north-east to a north-west wind. This descent of a
north-
east current of air producing a north-west wind may continue some
days
with clear or freezing weather, as it may be simply owing to a
vertical
eddy of north-east air, as will be spoken of below. It may
otherwise be
forced down by a current of south-west wind passing over it, and in
this
case it will be attended with rain for a few days by the mixture of
the
two airs of different degrees of heat; and will prognosticate a
change
of wind from north-east to south-west if the wind was previously in
the
north-east quarter.
3. On the eastern coast of North America the north-west winds bring
frost, as the north-east winds do in this country, as appears from
variety of testimony. This seems to happen from a vertical spiral
eddy
made in the atmosphere between the shore and the ridge of mountains
which form the spine or back-bone of that continent. If a current
of
water runs along the hypothenuse of a triangle an eddy will be made
in
the included angle, which will turn round like a water-wheel as the
stream passes in contact with one edge of it. The same must happen
when
a sheet of air flowing along from the north-east rises from the
shore in
a straight line to the summit of the Apalachian mountains, a part
of the
stream of north-east air will flow over the mountains, another part
will
revert and circulate spirally between the summit of the country and
the
eastern shore, continuing to move toward the south; and thus be
changed
from a north-east to a north-west wind.
This vertical spiral eddy having been in contact with the cold
summits
of these mountains, and descending from higher parts of the
atmosphere
will lose part of its heat, and thus constitute one cause of the
greater
coldness of the eastern sides of North America than of the European
shores opposite to them, which is said to be equal to twelve
degrees of
north latitude, which is a wonderful fact, not otherwise easy to be
explained, since the heat of the springs at Philadelphia is said to
be
50, which is greater than the medium heat of the earth in this
country.
The existence of vertical eddies, or great cylinders of air rolling
on
the surface of the earth, is agreeable to the observations of the
constructors of windmills; who on this idea place the area of the
sails
leaning backwards, inclined to the horizon; and believe that then
they
have greater power than when they are placed quite perpendicularly.
The
same kind of rolling cylinders of water obtain in rivers owing to
the
friction of the water against the earth at their bottoms; as is
known by
bodies having been observed to float upon their surfaces quicker
than
when immersed to a certain depth. These vertical eddies of air
probably
exist all over the earth's surface, but particularly at the bottom
or
sides of mountains; and more so probably in the course of the
south-west
than of the north-east winds; because the former fall from an
eminence,
as it were, on a part of the earth where there is a deficiency of
the
quantity of air; as is shewn by the sinking of the barometer:
whereas
the latter are pushed or squeezed forward by an addition to the
atmosphere behind them, as appears by the rising of the barometer.
TRADE-WINDS.
A column of heated air becomes lighter than before, and will
therefore
ascend, by the pressure of the cold air which surrounds it, like a
cork
in water, or like heated smoke in a chimney.
Now as the sun passes twice over the equator for once over either
tropic, the equator has not time to become cool; and on this
account it
is in general hotter at the line than at the tropics; and therefore
the
air over the line, except in some few instances hereafter to be
mentioned, continues to ascend at all seasons of the year, pressed
upwards by regions of air brought from the tropics.
This air thus brought from the tropics to the equator, would
constitute
a north wind on one side of the equator, and a south wind on the
other;
but as the surface of the earth at the equator moves quicker than
the
surface of the earth at the tropics, it is evident that a region of
air
brought from either tropic to the equator, and which had previously
only
acquired the velocity of the earth's surface at the tropics, will
now
move too slow for the earth's surface at the equator, and will
thence
appear to move in a direction contrary to the motion of the earth.
Hence
the trade-winds, though they consist of regions of air brought from
the
north on one side of the line, and from the south on the other,
will
appear to have the diagonal direction of north-east and south-west
winds.
Now it is commonly believed that there are superior currents of air
passing over these north-east and south-west currents in a contrary
direction, and which descending near the tropics produce vertical
whirlpools of air. An important question here again presents
itself,
What becomes of the moisture which this heated air ought to
deposit, as
it cools in the upper regions of the atmosphere in its journey to
the
tropics? It has been shewn by Dr. Priestley and Mr. Ingenhouz
that the
green matter at the bottom of cisterns, and the fresh leaves of
plants
immersed in water, give out considerable quantities of vital air in
the
sun-shine; that is, the perspirable matter of plants (which is
water
much divided in its egress from their minute pores) becomes
decomposed
by the sun's light, and converted into two kinds of air, the vital
and
inflammable airs. The moisture contained or dissolved in the
ascending
heated air at the line must exist in great tenuity; and by being
exposed
to the great light of the sun in that climate, the water may be
decomposed, and the new airs spread on the atmosphere from the line
to
the poles.
1. From there being no constant deposition of rains in the usual
course
of the trade-winds, it would appear that the water rising at the
line is
decomposed in its ascent.
2. From the observations of M. Bougner on the mountain Pinchinca,
one of
the Cordelieres immediately under the line, there appears to be no
condensible vapour above three or four miles high. Now though the
atmosphere at that height may be cold to a very considerable
degree; yet
its total deprivation of condensible vapour would seem to shew,
that its
water was decomposed; as there are no experiments to evince that
any
degree of cold hitherto known has been able to deprive air of its
moisture; and great abundance of snow is deposited from the air
that
flows to the polar regions, though it is exposed to no greater
degrees
of cold in its journey thither than probably exists at four miles
height
in the atmosphere at the line.
3. The hygrometer of Mr. Sauffure also pointed to dryness as he
ascended
into rarer air; the single hair of which it was constructed,
contracting
from deficiency of moisture. Essais sur l'Hygromet. p. 143.
From these observations it appears either that rare and cold air
requires more moisture to saturate it than dense air; or that the
moisture becomes decomposed and converted into air, as it ascends
into
these cold and rare regions of the atmosphere.
4. There seems some analogy between the circumstance of air being
produced or generated in the cold parts of the atmosphere both at
the
line and at the poles.
MONSOONS AND TORNADOES.
1. In the Arabian and Indian seas are winds, which blow six months
one
way, and six months the other, and are called Monsoons; by the
accidental dispositions of land and sea it happens, that in some
places
the air near the tropic is supposed to become warmer when the sun
is
vertical over it, than at the line. The air in these places
consequently ascends pressed upon one side by the north-east
regions of
air, and on the other side by the south-west regions of air. For as
the
air brought from the south has previously obtained the velocity of
the
earth's surface at the line, it moves faster than the earth's
surface
near the tropic where it now arrives, and becomes a south-west
wind,
while the air from the north becomes a north-east wind as before
explained. These two winds do not so quietly join and ascend as the
north-east and south-east winds, which meet at the line with equal
warmth and velocity and form the trade-winds; but as they meet in
contrary directions before they ascend, and cannot be supposed
accurately to balance each other, a rotatory motion will be
produced as
they ascend like water falling through a hole, and an horizontal or
spiral eddy is the consequence; these eddies are more or less
rapid, and
are called Tornadoes in their most violent state, raising water
from the
ocean in the west or sand from the deserts of the east, in less
violent
degrees they only mix together the two currents of north-east and
south-
west air, and produce by this means incessant rains, as the air of
the
north-east acquires some of the heat from the south-west wind, as
explained in Note XXV. This circumstance of the eddies produced by
the
monsoon-winds was seen by Mr. Bruce in Abyssinia; he relates that
for
many successive mornings at the commencement of the rainy monsoon,
he
observed a cloud of apparently small dimensions whirling round with
great rapidity, and in few minutes the heavens became covered with
dark
clouds with consequent great rains. See Note on Canto III. l. 129.
2. But it is not only at the place where the air ascends at the
northern
extremity of the rainy monsoon, and where it forms tornadoes, as
observed above by Mr. Bruce, but over a great tract of country
several
degrees in length in certain parts as in the Arabian sea, a
perpetual
rain for several months descends, similar to what happens for weeks
together in our own climate in a less degree during the south-west
winds. Another important question presents itself here, if the
climate
to which this south-west wind arrives, it not colder than that it
comes
from, why should it deposit its moisture during its whole journey?
if it
be a colder climate, why does it come thither? The tornadoes of
air
above described can extend but a little way, and it is not easy to
conceive that a superior cold current of air can mix with an
inferior
one, and thus produce showers over ten degrees of country, since at
about three miles high there is perpetual frost; and what can
induce
these narrow and shallow currents to flow over each other so many
hundred miles?
Though the earth at the northren extremity of this monsoon may be
more
heated by certain circumstances of situation than at the line, yet
it
seems probable that the intermediate country between that and the
line,
may continue colder than the line (as in other parts of the earth)
and
hence that the air coming from the line to supply this ascent or
destruction of air at the northern extremity of the monsoon will be
cooled all the way in its approach, and in consequence deposit its
water. It seems probable that at the northern extremity of this
monsoon,
where the tornadoes or hurricanes exist, that the air not only
ascends
but is in part converted into water, or otherwise diminished in
quantity, as no account is given of the existence of any superior
currents of it.
As the south-west winds are always attended with a light
atmosphere, an
incipient vacancy, or a great diminution of air must have taken
place to
the northward of them in all parts of the earth wherever they
exist, and
a deposition of their moisture succeeds their being cooled by the
climate they arrive at, and not by a contrary current of cold air
over
them, since in that case the barometer would not sink. They may
thus in
our own country be termed monsoons without very regular periods.
3. Another cause of TORNADOES independent of the monsoons is
ingeniously
explained by Dr. Franklin, when in the tropical countries a stratum
of
inferior air becomes so heated by its contact with the warm earth,
that
its expansion is increased more than is equivalent to the pressure
of
the stratum of air over it; or when the superior stratum becomes
more
condensed by cold than the inferior one by pressure, the upper
region
will descend and the lower one ascend. In this situation if one
part of
the atmosphere be hotter from some fortuitous circumstances, or,
has
less pressure over it, the lower stratum will begin to ascend at
this
part, and resemble water falling through a hole as mentioned above.
If
the lower region of air was going forwards with considerable
velocity,
it will gain an eddy by riling up this hole in the incumbent heavy
air,
so that the whirlpool or tornado has not only its progressive
velocity,
but its circular one also, which thus lifts up or overturns every
thing
within its spiral whirl. By the weaker whirlwinds in this country
the
trees are sometimes thrown down in a line of only twenty or forty
yards
in breadth, making a kind of avenue through a country. In the West
Indies the sea rises like a cone in the whirl, and is met by black
clouds produced by the cold upper air and the warm lower air being
rapidly mixed; whence are produced the great and sudden rains
called
water-spouts; while the upper and lower airs exchange their plus or
minus electricity in perpetual lightenings.
LAND AND SEA-BREEZES.
The sea being a transparent mass is less heated at its surface by
the
sun's rays than the land, and its continual change of surface
contributes to preserve a greater uniformity in the heat of the air
which hangs over it. Hence the surface of the tropical islands is
more
heated during the day than the sea that surrounds them, and cools
more
in the night by its greater elevation: whence in the afternoon when
the
lands of the tropical islands have been much heated by the sun, the
air
over them ascends pressed upwards by the cooler air of the
incircling
ocean, in the morning again the land becoming cooled more than the
sea,
the air over it descends by its increased gravity, and blows over
the
ocean near its shores.
CONCLUSION.
1. There are various irregular winds besides those above described,
which consist of horizontal or vertical eddies of air owing to the
inequality of the earth's surface, or the juxtaposition of the sea.
Other irregular winds have their origin from increased evaporation
of
water, or its sudden devaporation and descent in showers; others
from
the partial expansion and condensation of air by heat and cold; by
the
accumulation or defect of electric fluid, or to the air's new
production
or absorption occasioned by local causes not yet discovered. See
Notes
VII. and XXV.
2. There seem to exist only two original winds: one consisting of
air
brought from the north, and the other of air brought from the
south. The
former of these winds has also generally an apparent direction from
the
east, and the latter from the west, arising from the different
velocities of the earth's surface. All the other winds above
described
are deflections or retrogressions of some parts of these currents
of air
from the north or south.
3. One fifteenth part of the atmosphere is occasionally destroyed,
and
occasionally reproduced by unknown causes. These causes are brought
into
immediate activity over a great part of the surface of the earth at
nearly the same time, but always act more powerful to the northward
than
to the southward of any given place; and would hence seem to have
their
principal effect in the polar circles, existing nevertheless though
with
less power toward the tropics or at the line.
For when the north-east wind blows the barometer rises, sometimes
from
281/2 inches to 301/2, which shews a great new generation of air in
the
north; and when the south-west wind blows the barometer sinks as
much,
which shews a great destruction of air in the north. But as the
north-
east winds sometimes continue for five or six weeks, the
newly-generated
air must be destroyed at those times in the warmer climates to the
south
of us, or circulate in superior currents, which has been shewn to
be
improbable from its not depositing its water. And as the south-west
winds sometimes continue for some weeks, there must be a generation
of
air to the south at those times, or superior currents, which last
has
been shewn to be improbable.
4. The north-east winds being generated about the poles are pushed
forwards towards the tropics or line, by the pressure from behind,
and
hence they become warmer, as explained in Note VII. as well as by
their
coming into contact with a warmer part of the earth which
contributes to
make these winds greedily absorb moisture in their passage. On the
contrary, the south-west winds, as the atmosphere is suddenly
diminished
in the polar regions, are drawn as it were into an incipient
vacancy,
and become therefore expanded in their passage, and thus generate
cold,
as explained in Note VII. and are thus induced to part with their
moisture, as well as by their contact with a colder part of the
earth's
surface. Add to this, that the difference in the sound of the
north-east
and south-west winds may depend on the former being pushed forwards
by a
pressure behind, and the latter falling as it were into a partial
or
incipient vacancy before; whence the former becomes more condensed,
and
the latter more rarefied as it passes. There is a whistle, termed a
lark-call, which consists of a hollow cylinder of tin-plate, closed
at
each end, about half an inch in diameter and a quarter of an inch
high,
with opposite holes about the size of a goose-quill through the
centre
of each end; if this lark-whistle be held between the lips the
sound of
it is manifestly different when the breath is forceably blown
through it
from within outwards, and when it is sucked from without inwards.
Perhaps this might be worthy the attention of organ-builders.
5. A stop is put to this new generation of air, when about a
fifteenth
of the whole is produced, by its increasing pressure; and a similar
boundary is fixed to its absorption or destruction by the decrease
of
atmospheric pressure. As water requires more heat to convert it
into
vapour under a heavy atmosphere than under a light one, so in
letting
off the water from muddy fish-ponds great quantities of air-bubbles
are
seen to ascend from the bottom, which were previously confined
there by
the pressure of the water. Similar bubbles of inflammable air are
seen
to arise from lakes in many seasons of the year, when the
atmosphere
suddenly becomes light.
6. The increased absorptions and evolutions of air must, like its
simple
expansions, depend much on the presence or absence of heat and
light,
and will hence, in respect to the times and places of its
production and
destruction, be governed by the approach or retrocession of the
sun, and
on the temperature, in regard to heat, of various latitudes, and
parts
of the same latitude, so well explained by Mr. Kirwan.
7. Though the immediate cause of the destruction or reproduction of
great masses of air at certain times, when the wind changes from
north
to south, or from south to north can not yet be ascertained; yet as
there appears greater difficulty in accounting for this change of
wind
for any other known causes, we may still suspect that there exists
in
the arctic and antarctic circles a BEAR or DRAGON yet unknown to
philosophers, which at times suddenly drinks up, and as suddenly at
other times vomits out one-fifteenth part of the atmosphere: and
hope
that this or some future age will learn how to govern and
domesticate a
monster which might be rendered of such important service to
mankind.
INSTRUMENTS.
If along with the usual registers of the weather observations were
made
on the winds in many parts of the earth with the three following
instruments, which might be constructed at no great expence, some
useful
information might be acquired.
1. To mark the hour when the wind changes from north-east to
south-west,
and the contrary. This might be managed by making a communication
from
the vane of a weathercock to a clock; in such a manner, that if the
vane
mould revolve quite round, a tooth on its revolving axis should
stop the
clock, or put back a small bolt on the edge of a wheel revolving
once in
twenty-four hours.
2. To discover whether in a year more air passed from north to
south, or
the contrary. This might be effected by placing a windmill-sail of
copper about nine inches diameter in a hollow cylinder about six
inches
long, open at both ends, and fixed on an eminent situation exactly
north
and south. Thence only a part of the north-east and south-west
currents
would affect the sail so as to turn it; and if its revolutions were
counted by an adapted machinery, as the sail would turn one way
with the
north currents of air, and the contrary one with the south
currents, the
advance of the counting finger either way would shew which wind had
prevailed most at the end of the year.
3. To discover the rolling cylinders of air, the vane of a
weathercock
might be so suspended as to dip or rise vertically, as well as to
have
its horizontal rotation.
RECAPITULATION.
NORTH-EAST WINDS consist of air flowing from the north, where it
seems
to be occasionally produced; has an apparent direction from the
east
owing to its not having acquired in its journey the increasing
velocity
of the earth's surface; these winds are analogous to the
trade-winds
between the tropics, and frequently continue in the vernal months
for
four and six weeks together, with a high barometer, and fair or
frosty
weather. 2. They sometimes consist of south-west air, which had
passed
by us or over us, driven back by a new accumulation of air in the
north,
These continue but a day or two, and are attended with rain. See
Note
XXV.
SOUTH-WEST WIND consists of air flowing from the south, and seems
occasionally absorbed at its arrival to the more northern
latitudes. It
has a real direction from the west owing to its not having lost in
its
journey the greater velocity it had acquired from the earth's
surface
from whence it came. These winds are analogous to the monsoons
between
the tropics, and frequently continue for four or six weeks
together,
with a low barometer and rainy weather. 2. They sometimes consist
of
north-east air, which had passed by us or over us, which becomes
retrograde by a commencing deficiency of air in the north. These
winds
continue but a day or two, attended with severer frost with a
sinking
barometer; their cold being increased by their expansion, as they
return, into an incipient vacancy.
NORTH-WEST WINDS consist, first, of south-west winds, which have
passed
over us, bent down and driven back towards the south by newly
generated
northern air. They continue but a day or two, and are attended with
rain
or clouds. 2. They consist of north-east winds bent down from the
higher
parts of the atmosphere, and having there acquired a greater
velocity
than, the earth's surface; are frosty or fair. 3. They consist of
north-
east winds formed into a vertical spiral eddy, as on the eastern
coasts
of North America, and bring severe frost.
SOUTH-EAST WINDS consist, first, of north-east winds become
retrograde,
continue for a day or two, frosty or fair, sinking barometer. 2.
They
consist of north-east winds formed into a vertical eddy not a
spiral
one, frost or fair.
NORTH WINDS consist, first, of air flowing slowly from the north,
so
that they acquire the velocity of the earth's surface as they
approach,
are fair or frosty, seldom occur. 2. They consist of retrograde
south
winds; these continue but a day or two, are preceded by south-west
winds; and are generally succeeded by north-east winds, cloudy or
rainy,
barometer rising.
SOUTH WINDS consist, first, of air flowing slowly from the south,
loosing their previous western velocity by the friction of the
earth's
surface as they approach, moist, seldom occur, 2. They consist of
retrograde north winds; these continue but a day or two, are
preceded by
north-east winds, and generally succeeded by south-west winds,
colder,
barometer sinking.
EAST WINDS consist of air brought hastily from the north, and not
impelled farther southward, owing to a sudden beginning absorption
of
air in the northern regions, very cold, barometer high, generally
succeeded by south-west wind.
WEST WINDS consist of air brought hastily from the south, and
checked
from proceeding further to the north by a beginning production of
air in
the northern regions, warm and moist, generally succeeded by
north-east
wind. 2. They consist of air bent down from the higher regions of
the
atmosphere, if this air be from the south, and brought hastily it
becomes a wind of great velocity, moving perhaps 60 miles an hour,
is
warm and rainy; if it consists of northern air bent down it is of
less
velocity and colder.
Application of the preceding Theory to Some Extracts
from a Journal of the Weather.
Dec. 1, 1790. The barometer sunk suddenly, and the wind,
which had
been some days north-east with frost, changed to south-east with an
incessant though moderate fall of snow. A part of the northern air,
which had passed by us I suppose, now became retrograde before it
had
acquired the velocity of the earth's surface to the south of us,
and
being attended by some of the southern air in its journey, the
moisture
of the latter became condensed and frozen by its mixture mith the
former.
Dec. 2, 3. The wind changed to north-west and thawed the
snow. A part
of the southern air, which had passed by us or over us, with the
retrograde northern air above described, was now in its turn driven
back, before it had lost the velocity of the surface of the earth
to the
south of us, and consequently became a north-west wind; and not
having
lost the warmth it brought from the south produced a thaw.
Dec. 4, 5. Wind changed to north-east with frost and a
rising
barometer. The air from the north continuing to blow, after it had
driven back the southern air as above described, became a
north-east
wind, having less velocity than the surface of the earth in this
climate, and produced frost from its coldness.
Dec. 6, 7. Wind now changed to the south-west with incessant
rain and
a sinking barometer. From unknown causes I suppose the quantity of
air
to be diminished in the polar regions, and the southern air cooled
by
the earth's surface, which was previously frozen, deposits its
moisture
for a day or two; afterwards the wind continued south-west without
rain,
as the surface of the earth became warmer.
March 18, 1785. There has been a long frost; a few days ago
the
barometer sunk to 291/2, and the frost became more severe. Because
the air
being expanded by a part of the pressure being taken off became
colder.
This day the mercury rose to 30, and the frost ceased, the wind
continuing as before between north and east. March 19.
Mercury above
30, weather still milder, no frost, wind north-east. March 20.
The
same, for the mercury rising shews that the air becomes more
compressed
by the weight above, and in consequence gives out warmth.
April 4, 5. Frost, wind north-east, the wind changed in the
middle of
the day to the north-west without rain, and has done so for three
or
four days, becoming again north-east at night. For the sun now
giving
greater degrees of heat, the air ascends as the sun passes the
zenith,
and is supplied below by the air on the western side as well as on
the
eastern side of the zenith during the hot part of the day; whence
for a
few hours, on the approach of the hot part of the day, the air
acquires
a westerly direction in this longitude. If the north-west wind had
been
caused by a retrograde motion of some southern air, which had
passed
over us, it would have been attended with rain or clouds.
April 10. It rained all day yesterday, the wind north-west,
this
morning there was a sharp frost. The evaporation of the moisture,
(which
fell yesterday) occasioned by the continuance of the wind, produced
so
much cold as to freeze the dew.
May 12. Frequent showers with a current of colder wind
preceding every
shower. The sinking of the rain or cloud pressed away the air from
beneath it in its descent, which having been for a time shaded from
the
sun by the floating cloud, became cooled in some degree.
June 20. The barometer sunk, the wind became south-west, and
the whole
heaven was instantly covered with clouds. A part of the incumbent
atmosphere having vanished, as appeared by the sinking of the
barometer,
the remainder became expanded by its elasticity, and thence
attracted
some of the matter of heat from the vapour intermixed with it, and
thus
in a few minutes a total devaporation took place, as in exhausting
the
receiver of an air-pump. See note XXV. At the place where the air
is
destroyed, currents both from the north and south flow in to supply
the
deficiency, (for it has been shewn that there are no other proper
winds
but these two) and the mixture of these winds produces so sudden
condensation of the moisture, both by the coldness of the northern
air
and the expansion of both of them, that lightning is given out, and
an
incipient tornado takes place; whence thunder is said frequently to
approach against the wind.
August 28, 1732. Barometer was at 31, and Dec. 30, in
the same year,
it was at 28 2-tenths. Medical Essays, Edinburgh, Vol. II. p. 7. It
appears from these journals that the mercury at Edinburgh varies
sometimes nearly three inches, or one tenth of the whole
atmosphere.
From the journals kept by the Royal Society at London it appears
seldom
to vary more than two inches, or one-fifteenth of the whole
atmosphere.
The quantity of the variation is said still to decrease nearer the
line,
and to increase in the more northern latitudes; which much confirms
the
idea that there exists at certain times a great destruction or
production of air within the polar circle.
July 2, 1732. The westerly winds in the journal in the
Medical Essays,
Vol. II. above referred to, are frequently marked with the number
three
to shew their greater velocity, whereas the easterly winds seldom
approach to the number two. The greater velocity of the westerly
winds
than the easterly ones is well known I believe in every climate of
the
world; which may be thus explained from the theory above delivered.
1.
When the air is still, the higher parts of the atmosphere move
quicker
than those parts which touch the earth, because they are at a
greater
distance from the axis of motion. 2. The part of the atmosphere
where
the north or south wind comes from is higher than the part of it
where
it comes to, hence the more elevated parts of the atmosphere
continue to
descend towards the earth as either of those winds approach. 3.
When
southern air is brought to us it possesses a westerly direction
also,
owing to the velocity it had previously acquired from the earth's
surface; and if it consists of air from the higher parts of the
atmosphere descending nearer the earth, this westerly velocity
becomes
increased. But when northern air is brought to us, it possesses an
apparent easterly direction also, owing to the velocity which it
had
previously acquired from the earth's surface being less than that
of the
earth's surface in this latitude; now if the north-east wind
consists of
air descending from higher parts of the atmosphere, this deficiency
of
velocity will be less, in consequence of the same cause, viz. The
higher
parts of the atmosphere descending, as the wind approaches,
increases
the real velocity of the western winds, and decreases the apparent
velocity of the eastern ones.
October 22. Wind changed from south-east to south-west.
There is a
popular prognostication that if the wind changes from the north
towards
the south passing through the east, it is more likely to continue
in the
south, than if it passes through the west, which may be thus
accounted
for. If the north-east wind changes to a north-west wind, it shews
either that a part of the northern air descends upon us in a spiral
eddy, or that a superior current of southern air is driven back;
but if
a north-east wind be changed into a south-east wind it shews that
the
northern air is become retrograde, and that in a day or two, as
soon as
that part of it has passed, which has not gained the velocity of
the
earth's surface in this latitude, it will become a south wind for a
few
hours, and then a south-west wind.
The writer of this imperfect sketch of anemology wishes it may
incite
some person of greater leizure and ability to attend to this
subject,
and by comparing the various meteorological journals and
observations
already published, to construct a more accurate and methodical
treatise
on this interesting branch of philosophy.
And wed the enamoured Oxygene to Light.
CANTO IV. l. 34.
When points or hairs are put into spring-water, as in the
experiments of
Sir B. Thompson, (Philos. Trans. Vol. LXXVII.) and exposed to the
light
of the sun, much air, which loosely adhered to the water, rises in
bubbles, as explained in note on Fucus, Vol. II. A still greater
quantity of air, and of a purer kind, is emitted by Dr. Priestley's
green matter, and by vegetable leaves growing in water in the
sun-shine,
according to Mr. Ingenhouze's experiments; both which I suspect to
be
owing to a decomposition of the water perspired by the plant, for
the
edge of a capillary tube of great tenuity may be considered as a
circle
of points, and as the oxygene, or principle of vital air, may be
expanded into a gas by the sun's light; the hydrogene or
inflammable air
may be detained in the pores of the vegetable.
Hence plants growing in the shade are white, and become green by
being
exposed to the sun's light; for their natural colour being blue,
the
addition of hydrogene adds yellow to this blue, and tans
them green. I
suppose a similar circumstance takes place in animal bodies; their
perspirable matter as it escapes in the sun-shine becomes
decomposed by
the edges of their pores as in vegetables, though in less quantity,
as
their perspiration is less, and by the hydrogene being retained the
skin
becomes tanned yellow. In proof of this it must be observed
that both
vegetable and animal substances become bleached white by the
sun-beams
when they are dead, as cabbage-stalks, bones, ivory, tallow,
bees-wax,
linen and cotton cloth; and hence I suppose the copper-coloured
natives
of sunny countries might become etiolated or blanched by being kept
from
their infancy in the dark, or removed for a few generations to more
northerly climates.
It is probable that on a sunny morning much pure air becomes
separated
from the dew by means of the points of vegetables on which it
adheres,
and much inflammable air imbibed by the vegetable, or combined with
it;
and by the sun's light thus decomposing water the effects of it in
bleaching linen seems to depend (as described in Note X.): the
water is
decomposed by the light at the ends or points of the cotton or
thread,
and the vital air unites with the phlogistic or colouring matters
of the
cloth, and produces a new acid, which is either itself colourless
or
washes out, at the same time the inflammable part of the water
escapes.
Hence there seems a reason why cotton bleaches so much sooner than
linen, viz. because its fibres are three or four times shorter, and
therefore protrude so many more points, which seem to facilitate
the
liberation of the vital air from the inflammable part of the water.
Bee's wax becomes bleached by exposure to the sun and dews in a
similar
manner as metals become calcined or rusty, viz. by the water on
their
surface being decomposed; and hence the inflammable material which
caused the colour becomes united with vital air forming a new acid,
and
is washed away.
Oil close stopped in a phial not full, and exposed long to the
sun's
light, becomes bleached, as I suppose, by the decomposition of the
water
it contains; the inflammable air rising above the surface, and the
vital
air uniting with the colouring matter of the oil. For it is
remarkable,
that by shutting up a phial of bleached oil in a dark drawer, it in
a
little time becomes coloured again.
The following experiment shews the power of light in separating
vital
air from another basis, viz. from azote. Mr. Scheel inverted a
glass
vessel filled with colourless nitrous acid into another glass
containing
the same acid, and on exposing them to the sun's light, the
inverted
glass became partly filled with pure air, and the acid at the same
time
became coloured. Scheel in Crell's Annal. 1786. But if the vessel
of
colourless nitrous acid be quite full and stopped, so that no space
is
left for the air produced to expand itself into, no change of
colour
takes place. Priestley's Exp. VI. p. 344. See Keir's very excellent
Chemical Dictionary, p. 99. new edition.
A sun-flower three feet and half high according to the experiment
of Dr.
Hales, perspired two pints in one day (Vegetable Statics.) which is
many
times as much in proportion to its surface, as is perspired from
the
surface and lungs of animal bodies; it follows that the vital air
liberated from the surfaces of plants by the sunshine must much
exceed
the quantity of it absorbed by their respiration, and that hence
they
improve the air in which they live during the light part of the
day, and
thus blanched vegetables will sooner become tanned into green
by the
sun's light, than etiolated animal bodies will become tanned
yellow by
the same means.
It is hence evident, that the curious discovery of Dr. Priestley,
that
his green vegetable matter and other aquatic plants gave out vital
air
when the sun shone upon them, and the leaves of other plants did
the
same when immersed in water, as observed by Mr. Ingenhouze, refer
to the
perspiration of vegetables not to their respiration. Because Dr.
Priestley observed the pure air to come from both sides of the
leaves
and even from the stalks of a water-flag, whereas one side of the
leaf
only serves the office of lungs, and certainly not the stalks.
Exper. on
Air, Vol. III. And thus in respect to the circumstance in which
plants
and animals seemed the furtherest removed from each other, I mean
in
their supposed mode of respiration, by which one was believed to
purify
the air which the other had injured, they seem to differ only in
degree,
and the analogy between them remains unbroken.
Plants are said by many writers to grow much faster in the night
than in
the day; as is particularly observable in seedlings at their rising
out
of the ground. This probably is a consequence of their sleep rather
than
of the absence of light; and in this I suppose they also resemble
animal
bodies.
While in bright veins the silvery sap ascends.
CANTO IV. l. 419.
As buds are the viviparous offspring of vegetables, it becomes
necessary
that they should be furnished with placental vessels for their
nourishment, till they acquire lungs or leaves for the purpose of
elaborating the common juices of the earth into nutriment. These
vessels
exist in bulbs and in seeds, and supply the young plant with a
sweet
juice till it acquires leaves, as is seen in converting barley into
malt, and appears from the sweet taste of onions and potatoes, when
they
begin to grow.
The placental vessels belonging to the buds of trees are placed
about
the roots of most, as the vine; so many roots are furnished with
sweet
or mealy matter as fern-root, bryony, carrot, turnip, potatoe, or
in the
alburnum or sap-wood as in those trees which produce manna, which
is
deposited about the month of August, or in the joints of sugar
cane, and
grasses; early in the spring the absorbent mouths of these vessels
drink
up moisture from the earth, with a saccharine matter lodged for
that
purpose during the preceding autumn, and push this nutritive fluid
up
the vessels of the alburnum to every individual bud, as is evinced
by
the experiments of Dr. Hales, and of Mr. Walker in the Edinburgh
Philosophical Transact. The former observed that the sap from the
stump
of a vine, which he had cut off in the beginning of April, arose
twenty-
one feet high in tubes affixed to it for that purpose, but in a few
weeks it ceased to bleed at all, and Dr. Walker marked the progress
of
the ascending sap, and found likewise that as soon as the leaves
became
expanded the sap ceased to rise; the ascending juice of some trees
is so
copious and so sweet during the sap-season that it is used to make
wine,
as the birch, betula, and sycamore, acer pseudo-platinus, and
particularly the palm.
During this ascent of the sap-juice each individual leaf-bud
expands its
new leaves, and shoots down new roots, covering by their
intertexture
the old bark with a new one; and as soon as these new roots (or
bark)
are capable of absorbing sufficient juices from the earth for the
support of each bud, and the new leaves are capable of performing
their
office of exposing these juices to the influence of the air; the
placental vessels cease to act, coalesce, and are transformed from
sap-
wood, or alburnum, into inert wood; serving only for the support of
the
new tree, which grows over them.
Thus from the pith of the new bud of the horse-chesnut five vessels
pass
out through the circle of the placental vessels above described,
and
carry with them a minuter circle of those vessels; these five
bundles of
vessels unite after their exit, and form the footstalk or petiole
of the
new five-fingered leaf, to be spoken of hereafter. This structure
is
well seen by cutting off a leaf of the horse-chesnut (Aesculus
Hippocastanum) in September before it falls, as the buds of this
tree
are so large that the flower may be seen in them with the naked
eye.
After a time, perhaps about midsummer, another bundle of vessels
passes
from the pith through the alburnum or sap-vessels in the bosom of
each
leaf, and unites by the new bark with the leaf, which becomes
either a
flower-bud or a leaf-bud to be expanded in the ensuing spring, for
which
purpose an apparatus of placental vessels are produced with proper
nutriment during the progress of the summer and autumn, and thus
the
vegetable becomes annually increased, ten thousand buds often
existing
on one tree, according to the estimate of Linneus. Phil. Bot.
The vascular connection of vegetable buds with the leaves in whose
bosoms they are formed is confirmed by the following experiment,
(Oct.
20, 1781.) On the extremity of a young bud of the Mimosa (sensitive
plant) a small drop of acid of vitriol was put by means of a pen,
and,
after a few seconds, the leaf in whose axilla it dwelt closed and
opened
no more, though the drop of vitriolic acid was so small as
apparently
only to injure the summit of the bud. Does not this seem to shew
that
the leaf and its bud have connecting vessels though they arise at
different times and from different parts of the medulla or pith?
And, as
it exists previously to it, that the leaf is the parent of the bud?
This placentation of vegetable buds is clearly evinced from the
sweetness of the rising sap, and from its ceasing to rise as soon
as the
leaves are expanded, and thus compleats the analogy between buds
and
bulbs. Nor need we wonder at the length of the umbilical cords of
buds
since that must correspond with their situation on the tree, in the
same
manner as their lymphatics and arteries are proportionally
elongated.
It does not appear probable that any umbilical artery attends these
placental absorbents, since, as there seems to be no system of
veins in
vegetables to bring back the blood from the extremities of their
arteries, (except their pulmonary veins,) there could not be any
vegetable fluids to be returned to their placenta, which in
vegetables
seems to be simply an organ for nutrition, whereas the placenta of
the
animal foetus seems likewise to serve as a respiratory organ like
the
gills of fishes.
And refluent blood in milky eddies bends.
CANTO IV. l. 420.
The individuality of vegetable buds was spoken of before, and is
confirmed by the method of raising all kinds of trees by Mr.
Barnes.
(Method of propagating Fruit Trees. 1759. Lond. Baldwin.) He cut a
branch into as many pieces as there were buds or leaves upon it,
and
wiping the two wounded ends dry he quickly applied to each a
cement,
previously warmed a little, which consisted principally of pitch,
and
planted them in the earth. The use of this cement I suppose to
consist
in its preventing the bud from bleeding to death, though the author
ascribes it to its antisceptic quality.
These buds of plants, which are thus each an individual vegetable,
in
many circumstances resemble individual animals, but as animal
bodies are
detached from the earth, and move from place to place in search of
food,
and take that food at considerable intervals of time, and prepare
it for
their nourishiment within their own bodies after it is taken, it is
evident they must require many organs and powers which are not
necessary
to a stationary bud. As vegetables are immoveably fixed to the soil
from
whence they draw their nourishment ready prepared, and this
uniformly
not at returning intervals, it follows that in examining their
anatome
we are not to look for muscles of locomotion, as arms and legs; nor
for
organs to receive and prepare their nourishment, as a stomach and
bowels; nor for a reservoir for it after it is prepared, as a
general
system of veins, which in locomotive animals contains and returns
the
superfluous blood which is left after the various organs of
secretion
have been supplied, by which contrivance they are enabled to live a
long
time without new supplies of food.
The parts which we may expert to find in the anatome of vegetables
correspondent to those in the animal economy are, 1. A system of
absorbent vessels to imbibe the moisture of the earth similar to
the
lacteal vessels, as in the roots of plants; and another system of
absorbents similar to the lymphatics of animal bodies, opening its
mouths on the internal cells and external surfaces of vegetables;
and a
third system of absorbent vessels correspondent with those of the
placentation of the animal foetus. 2. A pulmonary system
correspondent
to the lungs or gills of quadrupeds and fish, by which the fluid
absorbed by the lacteals and lymphatics may be exposed to the
influence
of the air, this is done by the green leaves of plants, those in
the air
resembling lungs, and those in the water resembling gills; and by
the
petals of flowers. 3. Arterial systems to convey the fluid thus
elaborated to the various glands of the vegetable for the purposes
of
its growth, nutrition, and various secretions. 4. The various
glands
which separate from the vegetable blood the honey, wax, gum, resin,
starch, sugar, essential oil, &c. 5. The organs adapted for their
propagation or reproduction. 6. Muscles to perform several motions
of
their parts.
I. The existence of that branch of the absorbent vessels of
vegetables
which resembles the lacteals of animal bodies, and imbibes their
nutriment from the moist earth, is evinced by their growth so long
as
moisture is applied to their roots, and their quickly withering
when it
is withdrawn.
Besides these absorbents in the roots of plants there are others
which
open their mouths on the external surfaces of the bark and leaves,
and
on the internal surfaces of all the cells, and between the bark and
the
alburnum or sap-wood; the existence of these is shewn, because a
leaf
plucked off and laid with its under side on water will not wither
so
soon as if left in the dry air,—the same if the bark alone of a
branch
which is separated from a tree be kept moist with water,—and
lastly, by
moistening the alburnum or sap-wood alone of a branch detached from
a
tree it will not so soon wither as if left in the dry air. By the
following experiment these vessels were agreeably visible by a
common
magnifying glass, I placed in the summer of 1781 the footstalks of
some
large fig-leaves about an inch deep in a decoction of madder,
(rubia
tinctorum,) and others in a decoction of logwood, (haematoxylum
campechense,) along with some sprigs cut off from a plant of
picris,
these plants were chosen because their blood is white, after some
hours,
and on the next day, on taking out either of these and cutting off
from
its bottom about a quarter of an inch of the stalk an internal
circle of
red points appeared, which were the ends of absorbent vessels
coloured
red with the decoction, while an external ring of arteries was seen
to
bleed out hastily a milky juice, and at once evinced both the
absorbent
and arterial system. These absorbent vessels have been called by
Grew,
and Malphigi, and some other philosophers, bronchi, and erroneously
supposed to be air-vessels. It is probable that these vessels, when
cut
through, may effuse their fluids, and receive air, their sides
being too
stiff to collapse; since dry wood emits air-bubles in the exhausted
receiver in the same manner as moist wood.
The structure of these vegetable absorbents consists of a spiral
line,
and not of a vessel interrupted with valves like the animal
lymphatics,
since on breaking almost any tender leaf and drawing out some of
the
fibres which adhere longest this spiral structure becomes visible
even
to the naked eye, and distinctly so by the use of a common lens.
See
Grew, Plate 51.
In such a structure it is easy to conceive how a vermicular or
peristaltic motion of the vessel beginning at the lowest part of
it,
each spiral ring successively contracting itself till it fills up
the
tube, must forcibly push forwards its contents, as from the roots
of
vines in the bleeding season; and if this vermicular motion should
begin
at the upper end of the vessel it is as easy to see how it must
carry
its contained fluid in a contrary direction. The retrograde motion
of
the vegetable absorbent vessels is shewn by cutting a forked branch
from
a tree, and immersing a part of one of the forks in water, which
will
for many days prevent the other from withering; or it is shewn by
planting a willow branch with the wrong end upwards. This structure
in
some degree obtains in the esophagus or throat of cows, who by
similar
means convey their food first downwards and afterward upwards by a
retrograde motion of the annular muscles or cartilages for the
purpose
of a second mastication of it.
II. The fluids thus drank up by the vegetable absorbent vessels
from the
earth, or from the atmosphere, or from their own cells and
interfaces,
are carried to the foot-stalk of every leaf, where the absorbents
belonging to each leaf unite into branches, forming so many
pulmonary
arteries, and are thence dispersed to the extremities of the leaf,
as
may be seen in cutting away slice after slice the footstalk of a
horse-
chesnut in September before the leaf falls. There is then a
compleat
circulation in the leaf; a pulmonary vein receiving the blood from
the
extremities of each artery on the upper side of the leaf, and
joining
again in the footstalk of the leaf these veins produce so many
arteries,
or aortas, which disperse the new blood over the new bark,
elongating
its vessels, or producing its secretions; but as a reservoir of
blood
could not be wanted by a vegetable bud which takes in its nutriment
at
all times, I imagine there is no venous system, no veins properly
so
called, which receive the blood which was to spare, and return it
into
the pulmonary or arterial system.
The want of a system of veins was countenanced by the following
experiment; I cut off several stems of tall spurge, (Euphorbia
helioscopia) in autumn, about the centre of the plant, and observed
tenfold the quantity of milky juice ooze from the upper than from
the
lower extremity, which could hardly have happened if there had been
a
venous system of vessels to return the blood from the roots to the
leaves.
Thus the vegetable circulation, complete in the lungs, but probably
in
the other part of the system deficient in respect to a system of
returning veins, is carried forwards without a heart, like the
circulation through the livers of animals where the blood brought
from
the intestines and mesentery by one vein is dispersed through the
liver
by the vena portarum, which assumes the office of an artery. See
Note
XXXVII.
At the same time so minute are the vessels in the intertexture of
the
barks of plants, which belong to each individual bud, that a
general
circulation may possibly exist, though we have not yet been able to
discover the venous part of it.
There is however another part of the circulation of vegetable
juices
visible to the naked eye, and that is in the corol or petals of
flowers,
in which a part of the blood of the plant is exposed to the
influence of
the air and light in the same manner as in the foliage, as will be
mentioned more at large in Notes XXXVII and XXXIX.
These circulations of their respective fluids seem to be carried on
in
the vessels of plants precisely as in animal bodies by their
irritability to the stimulus of their adapted fluids, and not by
any
mechanical or chemical attraction, for their absorbent vessels
propel
the juice upwards, which they drink up from the earth, with great
violence; I suppose with much greater than is exerted by the
lacteals of
animals, probably owing to the greater minuteness of these vessels
in
vegetables and the greater rigidity of their coats. Dr. Hales in
the
spring season cut off a vine near the ground, and by fixing tubes
on the
remaining stump of it, found the sap to rise twenty-one feet in the
tube
by the propulsive power of these absorbents of the roots of it.
Veget.
Stat. p. 102. Such a power can not be produced by capillary
attraction,
as that could only raise a fluid nearly to the upper edge of the
attracting cylinder, but not enable it to flow over that edge, and
much
less to rise 21 feet above it. What then can this power be owing
to?
Doubtless to the living activity of the absorbent vessels, and to
their
increased vivacity from the influence of the warmth of the spring
succeeding the winter's cold, and their thence greater
susceptibility to
irritation from the juices which they absorb, resembling in all
circumstances the action of the living vessels of animals.
While spread in air the leaves respiring play.
CANTO IV. l. 421.
I. There have been various opinions concerning the use of the
leaves of
plants in the vegetable oeconomy. Some have contended that they are
perspiratory organs; this does not seem probable from an experiment
of
Dr. Hales, Veg. Stat. p. 30. He found by cutting off branches of
trees
with apples on them, and taking off the leaves, that an apple
exhaled
about as much as two leaves, the surfaces of which were nearly
equal to
the apple; whence it would appear that apples have as good a claim
to be
termed perspiratory organs as leaves. Others have believed them
excretory organs of excrementious juices; but as the vapour exhaled
from
vegetables has no taste, this idea is no more probable than the
other;
add to this that in moist weather, they do not appear to perspire
or
exhale at all.
The internal surface of the lungs or air-vessels in men, are said
to be
equal to the external surface of the whole body, or about fifteen
square
feet; on this surface the blood is exposed to the influence of the
respired air through the medium however of a thin pellicle; by this
exposure to the air it has its colour changed from deep red to
bright
scarlet, and acquires something so necessary to the existence of
life,
that we can live scarcely a minute without this wonderful process.
The analogy between the leaves of plants and the lungs or gills of
animals seems to embrace so many circumstances, that we can
scarcely
withhold our assent to their performing similar offices.
I. The great surface of the leaves compared to that of the trunk
and
branches of trees is such, that it would seem to be an organ well
adapted for the purpose of exposing the vegetable juices to the
influence of the air; this however we shall see afterwards is
probably
performed only by their upper surfaces, yet even in this case the
surface of the leaves in general bear a greater proportion to the
surface of the tree, than the lungs of animals to their external
surfaces.
2. In the lungs of animal, the blood after having been exposed to
the
air in the extremities of pulmonary artery, is changed in colour
from
deep red to bright scarlet, and certainly in some of its essential
properties; it is then collected by the pulmonary vein and returned
to
the heart. To shew a similarity of circumstance in the leaves of
plants
the following experiment was made, June 24, 1781: A stalk with
leaves
and seed-vessels of large spurge (Euphorbia helioscopia) had been
several days placed in a decoction of madder (Rubia tinctorum) so
that
the lower part of the stem, and two of the undermost leaves were
immersed in it. After having washed the immersed leaves in clear
water,
I could readily discern the colour of the madder passing along the
middle rib of each leaf. This red artery was beautifully visible
both on
the under and upper surface of the leaf; but on the upper side many
red
branches were seen going from it to the extremities of the leaf,
which
on the other side were not visible except by looking through it
against
the light. On this under side a system of branching vessels
carrying a
pale milky fluid were seen coming from the extremities of the leaf,
and
covering the whole underside of it, and joining into two large
veins,
one on each side of the red artery in the middle rib of the leaf,
and
along with it descending to the footstalk or petiole. On slitting
one of
these leaves with scissars, and having a common magnifying lens
ready,
the milky blood was seen oozing out of the returning veins on each
side
of the red artery in the middle rib, but none of the red fluid from
the
artery.
All these appearances were more easily seen in a leaf of Picris
treated
in the same manner; for in this milky plant the stems and middle
rib of
the leaves are sometimes naturally coloured reddish, and hence the
colour of the madder seemed to pass further into the ramifications
of
their leaf-arteries, and was there beautifully visible with the
returning branches of milky veins on each side.
3. From these experiments the upper surface of the leaf appeared to
be
the immediate organ of respiration, because the coloured fluid was
carried to the extremities of the leaf by vessels most conspicuous
on
the upper surface, and there changed into a milky fluid, which is
the
blood of the plant, and then returned by concomitant veins on the
under
surface, which were seen to ooze when divided with scissars, and
which
in Picris, particularly render the under surface of the leaves
greatly
whiter than the upper one.
4. As the upper surface of leaves constitutes the organ of
respiration,
on which the sap is exposed in the terminations of arteries beneath
a
thin pellicle to the action of the atmosphere, these surfaces in
many
plants strongly repel moisture, as cabbage-leaves, whence the
particles
of rain lying over their surfaces without touching them, as
observed by
Mr. Melville (Essays Literary and Philosop. Edinburgh) have the
appearance of globules of quicksilver. And hence leaves laid with
the
upper surfaces on water, wither as soon as in the dry air, but
continue
green many days, if placed with the under surfaces on water, as
appears
in the experiments of Mons. Bonnet (Usage des Fevilles.) Hence some
aquatic plants, as the Water-lily (Nymphoea) have the lower sides
of
their leaves floating on the water, while the upper surfaces remain
dry
in the air.
5. As those insects, which have many spiracula, or breathing
apertures,
as wasps and flies, are immediately suffocated by pouring oil upon
them, I carefully covered with oil the surfaces of several leaves
of
Phlomis, of Portugal Laurel, and Balsams, and though it would not
regularly adhere, I found them all die in a day or two.
Of aquatic leaves, see Note on Trapa and on Fucus, in Vol. II. to
which
must be added that many leaves are furnished with muscles about
their
footstalks, to turn their upper surfaces to the air or light, as
Mimosa
and Hedysarum gyrans. From all these analogies I think there can be
no
doubt but that leaves of trees are their lungs, giving out a
phlogistic
material to the atmosphere, and absorbing oxygene or vital air.
6. The great use of light to vegetation would appear from this
theory to
be by disengaging vital air from the water which they perspire, and
thence to facilitate its union with their blood exposed beneath the
thin
surface of their leaves; since when pure air is thus applied, it is
probable, that it can be more readily absorbed. Hence in the
curious
experiments of Dr. Priestley and Mr. Ingenhouze, some plants
purified
air less than others, that is, they perspired less in the sunshine;
and
Mr. Scheele found that by putting peas into water, which about
half-
covered them, that they converted the vital air into fixed air, or
carbonic acid gas, in the same manner as in animal respiration. See
Note
XXXIV.
7. The circulation in the lungs or leaves of plants is very similar
to
that of fish. In fish the blood after having passed through their
gills
does not return to the heart as from the lungs of air-breathing
animals,
but the pulmonary vein taking the structure of an artery after
having
received the blood from the gills, which there gains a more florrid
colour, distributes it to the other parts of their bodies. The same
structure occurs in the livers of fish, whence we see in those
animals
two circulations independent of the power of the heart, viz. that
beginning at the termination of the veins of the gills, and
branching
through the muscles; and that which passes through the liver; both
which
are carried on by the action of those respective arteries and
veins.
Monro's Physiology of Fish, p. 19.
The course of the fluids in the roots, leaves, and buds of
vegetables
seems to be performed in a manner similar to both these. First the
absorbent vessels of the roots and surfaces unite at the footstalk
of
the leaf; and then, like the Vena Portarum, an artery commences
without
the intervention of a heart, and spreads the sap in its numerous
ramifications on the upper surface of the leaf; here it changes its
colour and properties, and becomes vegetable blood; and is again
collected by a pulmonary vein on the under surface of the leaf.
This
vein, like that which receives the blood from the gills of fish,
assumes
the office and name of an artery, and branching again disperses the
blood upward to the bud from the footstalk of the leaf, and
downward to
the roots; where it is all expended in the various secretions, the
nourishment and growth of the plant, as fast as it is prepared.
II. The organ of respiration already spoken of belongs particularly
to
the shoots or buds, but there is another pulmonary system, perhaps
totally independent of the green foliage, which belongs to the
fructification only, I mean the corol or petals. In this there is
an
artery belonging to each petal, which conveys the vegetable blood
to its
extremities, exposing it to the light and air under a delicate
membrane
covering the internal surface of the petal, where it often changes
its
colour, as is beautifully seen in some party-coloured poppies;
though it
is probable some of the iridescent colours of flowers may be owing
to
the different degrees of tenuity of the exterior membrane of the
leaf
refracting the light like soap-bubbles, the vegetable blood is then
returned by correspondent vegetable veins, exactly as in the green
foliage; for the purposes of the important secretions of honey,
wax, the
finer essential oil, and the prolific dust of the anthers.
1. The vascular structure of the corol as above described, and
which is
visible to the naked eye, and its exposing the vegetable juices to
the
air and light during the day, evinces that it is a pulmonary organ.
2. As the glands which produce the prolific dust of the anthers,
the
honey, wax, and frequently some odoriferous essential oil, are
generally
attached to the corol, and always fall off and perish with it, it
is
evident that the blood is elaborated or oxygenated in this
pulmonary
system for the purpose of these important secretions.
3. Many flowers, as the Colchicum, and Hamamelis arise naked in
autumn,
no green leaves appearing till the ensuing spring; and many others
put
forth their flowers and complete their impregnation early in the
spring
before the green foliage appears, as Mezereon, cherries, pears,
which
shews that these corols are the lungs belonging to the
fructification.
4. This organ does not seem to have been necessary for the defence
of
the stamens and pistils, since the calyx of many flowers, as
Tragopogon,
performs this office; and in many flowers these petals themselves
are so
tender as to require being shut up in the calyx during the night,
for
what other use then can such an apparatus of vessels be designed?
5. In the Helleborus-niger, Christmas-rose, after the seeds are
grown to
a certain size, the nectaries and stamens drop off, and the
beautiful
large white petals change their colour to a deep green, and
gradually
thus become a calyx inclosing and defending the ripening seeds,
hence it
would seem that the white vessels of the corol served the office of
exposing the blood to the action of the air, for the purposes of
separating or producing the honey, wax, and prolific dust, and when
these were no longer wanted, that these vessels coalesced like the
placental vessels of animals after their birth, and thus ceased to
perform that office and lost at the same time their white colour.
Why
should they loose their white colour, unless they at the same time
lost
some other property besides that of defending the seed-vessel,
which
they still continue to defend?
6. From these observations I am led to doubt whether green leaves
be
absolutely necessary to the progress of the fruit-bud after the
last
year's leaves are fallen off. The green leaves serve as lungs to
the
shoots and foster the new buds in their bosoms, whether these buds
be
leaf-buds or fruit-buds; but in the early spring the fruit-buds
expand
their corols, which are their lungs, and seem no longer to require
green
leaves; hence the vine bears fruit at one joint without leaves, and
puts
out a leaf-bud at another joint without fruit. And I suppose the
green
leaves which rise out of the earth in the spring from the Colchicum
are
for the purpose of producing the new bulb, and its placenta, and
not for
the giving maturity to the seed. When currant or goosberry trees
lose
their leaves by the depredation of insects the fruit continues to
be
formed, though less sweet and less in size.
7. From these facts it appears that the flower-bud after the corol
falls
off, (which is its lungs,) and the stamens and nectary along with
it,
becomes simply an uterus for the purpose of supplying the growing
embryon with nourishment, together with a system of absorbent
vessels
which bring the juices of the earth to the footstalk of the fruit,
and
which there changes into an artery for the purpose of distributing
the
sap for the secretion of the saccharine or farinaceous or acescent
materials for the use of the embryon. At the same time as all the
vessels of the different buds of trees inosculate or communicate
with
each other, the fruit becomes sweeter and larger when the green
leaves
continue on the tree, but the mature flowers themselves, (the
succeeding
fruit not considered) perhaps suffer little injury from the green
leaves
being taken off, as some florists have observed.
8. That the vessels of different vegetable buds inosculate in
various
parts of their circulation is rendered probable by the increased
growth
of one bud, when others in its vicinity are cut away; as it thus
seems
to receive the nourishment which was before divided amongst many.
Love out their hour and leave their lives in air.
CANTO IV. l. 456.
From the accurate experiments and observations of Spallanzani it
appears
that in the Spartium Junceum, rush-broom, the very minute seeds
were
discerned in the pod at least twenty days before the flower is in
full
bloom, that is twenty days before fecundation. At this time also
the
powder of the anthers was visible, but glued fast to their summits.
The
seeds however at this time, and for ten days after the blossom had
fallen off, appeared to consist of a gelatinous substance. On the
eleventh day after the falling of the blossom the seeds became
heart-
shape, with the basis attached by an appendage to the pod, and a
white
point at the apex; this white point was on pressure found to be a
cavity
including a drop of liquor.
On the 25th day the cavity which at first appeared at the apex was
much
enlarged and still full of liquor, it also contained a very small
semi-
transparent body, of a yellowish colour, gelatinous, and fixed by
its
two opposite ends to the sides of the cavity.
In a month the seed was much enlarged and its shape changed from a
heart
to a kidney, the little body contained in the cavity was increased
in
bulk and was less transparent, and gelatinous, but there yet
appeared no
organization.
On the 40th day the cavity now grown larger was quite filled with
the
body, which was covered with a thin membrane; after this membrane
was
removed the body appeared of a bright green, and was easily divided
by
the point of a needle into two portions, which manifestly formed
the two
lobes, and within these attached to the lower part the exceedingly
small
plantule was easily perceived.
The foregoing observations evince, 1. That the seeds exist in the
ovarium many days before fecundation. 2. That they remain for some
time
solid, and then a cavity containing a liquid is formed in them. 3.
That
after fecundation a body begins to appear within the cavity fixed
by two
points to the sides, which in process of time proves to be two
lobes
containing a plantule. 4. That the ripe seed consists of two lobes
adhering to a plantule, and surrounded by a thin membrane which is
itself covered with a husk or cuticle. Spalanzani's Dissertations,
Vol.
II. p. 253.
The analogy between seeds and eggs has long been observed, and is
confirmed by the mode of their production. The egg is known to be
formed
within the hen long before its impregnation; C.F. Wolf asserts that
the
yolk of the egg is nourished by the vessels of the mother, and that
it
has from those its arterial and venous branches, but that after
impregnation these vessels gradually become impervious and
obliterated,
and that new ones are produced from the fetus and dispersed into
the
yolk. Haller's Physiolog. Tom. VIII. p. 94. The young seed after
fecundation, I suppose, is nourished in a similar manner from the
gelatinous liquor, which is previously deposited for that purpose;
the
uterus of the plant producing or secreting it into a reservoir or
amnios
in which the embryon is lodged, and that the young embryon is
furnished
with vessels to absorb a part of it, as in the very early embryon
in the
animal uterus.
The spawn of frogs and of fish is delivered from the female before
its
impregnation. M. Bonnet says that the male salamander darts his
semen
into the water, where it forms a little whitish cloud which is
afterwards received by the swoln anus of the female, and she is
fecundated.—He adds that marine plants approach near to these
animals,
as the male does not project a fine powder but a liquor which in
like
manner forms a little cloud in the water.—And further adds, who
knows
but the powder of the stamina of certain plants may not make some
impression on certain germs belonging to the animal kingdom! Letter
XLIII. to Spalanzani, Oevres Philos.
Spalanzani found that the seminal fluid of frogs and dogs even when
diluted with much water retained its prolific quality. Whether this
quality be simply a stimulus exciting the egg into animal action,
which
may be called a vivifying principle, or whether part of it be
actually
conjoined with the egg is not yet determined, though the latter
seems
more probable from the frequent resemblance of the fetus to the
male
parent. A conjunction however of both the male and female influence
seems necessary for the purpose of reproduction throughout all
organized
nature, as well in hermaphrodite insects, microscopic animals, and
polypi, and exists as well in the formation of the buds of
vegetables as
in the production of their seeds, which is ingeniously conceived
and
explained by Linneus. After having compared the flower to the larva
of a
butterfly, confining of petals instead of wings, calyxes instead of
wing-sheaths, with the organs of reproduction, and having shewn the
use
of the farina in fecundating the egg or seed, he proceeds to
explain the
production of the bud. The calyx of a flower, he says, is an
expansion
of the outer bark, the petals proceed from the inner bark or rind,
the
stamens from the alburnum or woody circle, and the style from the
pith.
In the production and impregnation of the seed a commixture of the
secretions of the stamens and style are necessary; and for the
production of a bud he thinks the medulla or pith bursts its
integuments
and mixes with the woody part or alburnum, and these forcing their
passage through the rind and bark constitute the bud or viviparous
progeny of the vegetable. System of Vegetables translated from
Linneus,
p. 8.
It has been supposed that the embryon vegetable after fecundation,
by
its living activity or stimulus exerted on the vessels of the
parent
plant, may produce the fruit or seed-lobes, as the animal fetus
produces
its placenta, and as vegetable buds may be supposed to produce
their
umbilical vessels or roots down the bark of the tree. This in
respect to
the production of the fruit surrounding the seeds of trees has been
assimilated to the gall-nuts on oak-leaves, and to the bedeguar on
briars, but there is a powerful objection to this doctrine, viz.
that
the fruit of figs, all which are female in this country, grow
nearly as
large without fecundation, and therefore the embryon has in them no
self-living principle.
Seeks, where fine pores their dulcet balm distil.
CANTO IV. l. 503.
The glands of vegetables which separate from their blood the
mucilage,
starch, or sugar for the placentation or support of their seeds,
bulbs,
and buds; or those which deposit their bitter, acrid, or narcotic
juices
for their defence from depredations of insects or larger animals;
or
those which secrete resins or wax for their protection from
moisture or
frosts, consist of vessels too fine for the injection or absorption
of
coloured fluids, and have not therefore yet been exhibited to the
inspection even of our glasses, and can therefore only be known by
their
effects, but one of the most curious and important of all vegetable
secretions, that of honey, is apparent to our naked eyes, though
before
the discoveries of Linneus the nectary or honey-gland had not even
acquired a name.
The odoriferous essential oils of several flowers seem to have been
designed for their defence against the depredations of insects,
while
their beautiful colours were a necessary consequence of the size of
the
particles of their blood, or of the tenuity of the exterior
membrane of
the petal. The use of the prolific dust is now well ascertained,
the wax
which covers the anthers prevents this dust from receiving
moisture,
which would make it burst prematurely and thence prevent its
application
to the stigma, as sometimes happens in moist years and is the cause
of
deficient fecundation both of our fields and orchards.
The universality of the production of honey in the vegetable world,
and
the very complicated apparatus which nature has constructed in many
flowers, as well as the acrid or deleterious juices she has
furnished
those flowers with (as in the Aconite) to protect this honey from
rain
and from the depredations of insects, seem to imply that this fluid
is
of very great importance in the vegetable economy; and also that it
was
necessary to expose it to the open air previous to its reabsorption
into
the vegetable vessels.
In the animal system the lachrymal gland separates its fluid into
the
open air for the purpose of moistening the eye, of this fluid the
part
which does not exhale it absorbed by the puncta lachrymalia and
carried
into the nostrils; but as this is not a nutritive fluid the analogy
goes
no further than its secretion into the open air and its
reabsorption
into the system; every other secreted fluid in the animal body is
in
part absorbed again into the system, even those which are esteemed
excrementitious, as the urine and perspirable matter, of which the
latter is secreted, like the honey, into the external air. That the
honey is a nutritious fluid, perhaps the most so of any vegetable
production, appears from its great similarity to sugar, and from
its
affording sustenance to such numbers of insects, which live upon it
solely during summer, and lay it up for their winter provision.
These
proofs of its nutritive nature evince the necessity of its
reabsorption
into the vegetable system for some useful purpose.
This purpose however has as yet escaped the researches of
philosophical
botanists. M. Pontedera believes it designed to lubricate the
vegetable
uterus, and compares the horn-like nectaries of some flowers to the
appendicle of the caecum intestinum of animals. (Antholog. p. 49.)
Others have supposed that the honey, when reabsorbed, might serve
the
purpose of the liquor amnii, or white of the egg, as a nutriment
for the
young embryon or fecundated seed in its early state of existence.
But as
the nectary is found equally general in male flowers as in female
ones;
and as the young embryon or seed grows before the petals and
nectary are
expanded, and after they fall off; and, thirdly, as the nectary so
soon
falls off after the fecundation of the pistillum; these seem to be
insurmountable objections to both the above-mentioned opinions.
In this state of uncertainty conjectures may be of use so far as
they
lead to further experiment and investigation. In many tribes of
insects,
as the silk-worm, and perhaps in all the moths and butterflies, the
male
and female parents die as soon as the eggs are impregnated and
excluded;
the eggs remaining to be perfected and hatched at some future time.
The
same thing happens in regard to the male and female parts of
flowers;
the anthers and filaments, which constitute the male parts of the
flower, and the stigma and style, which constitute the female part
of
the flower, fall off and die as soon as the seeds are impregnated,
and
along with these the petals and nectary. Now the moths and
butterflies
above-mentioned, as soon as they acquire the passion and the
apparatus
for the reproduction of their species, loose the power of feeding
upon
leaves as they did before, and become nourished by what?—by honey
alone.
Hence we acquire a strong analogy for the use of the nectary or
secretion of honey in the vegetable economy, which is, that the
male
parts of flowers, and the female parts, as soon as they leave their
fetus-state, expanding their petals, (which constitute their
lungs,)
become sensible to the passion, and gain the apparatus for the
reproduction of their species, and are fed and nourished with honey
like
the insects above described; and that hence the nectary begins its
office of producing honey, and dies or ceases to produce honey at
the
same time with the birth and death of the stamens and the pistils;
which, whether existing in the same or in different flowers, are
separate and distinct animated beings.
Previous to this time the anthers with their filaments, and the
stigmas
with their styles, are in their fetus-state sustained by their
placental
vessels, like the unexpanded leaf-bud; with the seeds existing in
the
vegetable womb yet unimpregnated, and the dust yet unripe in the
cells
of the anthers. After this period they expand their petals, which
have
been shewn above to constitute the lungs of the flower; the
placental
vessels, which before nourished the anthers and the stigmas,
coalesce or
cease to nourish them; and they now acquire blood more oxygenated
by the
air, obtain the passion and power of reproduction, are sensible to
heat,
and cold, and moisture, and to mechanic stimulus, and become in
reality
insects fed with honey, similar in every respect except their being
attached to the tree on which they were produced.
Some experiments I have made this summer by cutting out the
nectaries of
several flowers of the aconites before the petals were open, or had
become much coloured, some of these flowers near the summit of the
plants produced no seeds, others lower down produced seeds; but
they
were not sufficiently guarded from the farina of the flowers in
their
vicinity; nor have I had opportunity to try if these seeds would
vegetate.
I am acquainted with a philosopher, who contemplating this subject
thinks it not impossible, that the first insects were the anthers
or
stigmas of flowers; which had by some means loosed themselves from
their
parent plant, like the male flowers of Vallisneria; and that many
other
insects have gradually in long process of time been formed from
these;
some acquiring wings, others fins, and others claws, from their
ceaseless efforts to procure their food, or to secure themselves
from
injury. He contends, that none of these changes are more
incomprehensible than the transformation of tadpoles into frogs,
and
caterpillars into butterflies.
There are parts of animal bodies, which do not require oxygenated
blood
for the purpose of their secretions, as the liver; which for the
production of bile takes its blood from the mesenteric veins, after
it
must have lost the whole or a great part of its oxygenation, which
it
had acquired in its passage through the lungs. In like manner the
pericarpium, or womb of the flower, continues to secrete its proper
juices for the present nourishment of the newly animated
embryon-seed;
and the saccharine, acescent, or starchy matter of the fruit or
seed-
lobes for its future growth; in the same manner as these things
went on
before fecundation; that is, without any circulation of juices in
the
petals, or production of honey in the nectary; these having
perished and
fallen off with the male and female apparatus for impregnation.
It is probable that the depredations of insects on this nutritious
fluid
must be injurious to the products of vegetation, and would be much
more
so, but that the plants have either acquired means to defend their
honey
in part, or have learned to make more than is absolutely necessary
for
their own economy. In the same manner the honey-dew on trees is
very
injurious to them; in which disease the nutritive fluid, the
vegetable-
sap-juice, seems to be exsuded by a retrograde motion of the
cutaneous
lymphatics, as in the sweating sickness of the last century. To
prevent
the depredation of insects on honey a wealthy man in Italy is said
to
have poisoned his neighbour's bees perhaps by mixing arsnic with
honey,
against which there is a most flowery declamation in Quintilian.
No.
XIII. As the use of the wax is to preserve the dust of the anthers
from
moisture, which would prematurely burst them, the bees which
collect
this for the construction of the combs or cells, must on this
account
also injure the vegetation of a country where they too much abound.
It is not easy to conjecture why it was necessary that this
secretion of
honey should be exposed to the open air in the nectary or
honey-cup, for
which purpose so great an apparatus for its defence from insects
and
from showers became necessary. This difficulty increases when we
recollect that the sugar in the joints of grass, in the sugar-cane,
and
in the roots of beets, and in ripe fruits is produced without the
exposure to the air. On supposition of its serving for nutriment to
the
anthers and stigmas it may thus acquire greater oxygenation for the
purpose of producing greater powers of sensibility, according to a
doctrine lately advanced by a French philosopher, who has
endeavoured to
shew that the oxygene, or base of vital air, is the constituent
principle of our power of sensibility.
From this provision of honey for the male and female parts of
flowers,
and from the provision of sugar, starch, oil, and mucilage, in the
fruits, seed-cotyledons, roots, and buds of plants laid up for the
nutriment of the expanding fetus, not only a very numerous class of
insects, but a great part of the larger animals procure their food;
and
thus enjoy life and pleasure without producing pain to others, for
these
seeds or eggs with the nutriment laid up in them are not yet endued
with
sensitive life.
The secretions from various vegetable glands hardened in the air
produce
gums, resins, and various kinds of saccharine, saponaceous, and
wax-like
substances, as the gum of cherry or plumb-trees, gum tragacanth
from the
astragalus tragacantha, camphor from the laurus camphora, elemi
from
amyris elemifera, aneme from hymenoea courbaril, turpentine from
pistacia terebinthus, balsam of Mecca from the buds of amyris
opobalsamum, branches of which are placed in the temples of the
East on
account of their fragrance, the wood is called xylobalsamum, and
the
fruit carpobalsamum; aloe from a plant of the same name; myrrh from
a
plant not yet described; the remarkably elastic resin is brought
into
Europe principally in the form of flasks, which look like black
leather,
and are wonderfully elastic, and not penetrable by water, rectified
ether dissolves it; its flexibility is encreased by warmth and
destroyed
by cold; the tree which yields this juice is the jatropha elastica,
it
grows in Guaiana and the neighbouring tracts of America; its juice
is
said to resemble wax in becoming soft by heat, but that it acquires
no
elasticity till that property is communicated to it by a secret
art,
after which it is poured into moulds and well dried and can no
longer be
rendered fluid by heat. Mr. de la Borde physician at Cayenne has
given
this account. Manna is obtained at Naples from the fraxinus ornus,
or
manna-ash, it partly issues spontaneously, which is preferred, and
partly exsudes from wounds made purposely in the month of August,
many
other plants yield manna more sparingly; sugar is properly made
from the
saccharum officinale, or sugar-cane, but is found in the roots of
beet
and many other plants; American wax is obtained from the myrica
cerifera, candle-berry myrtle, the berries are boiled in water and
a
green wax separates, with luke-warm water the wax is yellow: the
seed of
croton sebiferum are lodged in tallow; there are many other
vegetable
exsudations used in the various arts of dyeing, varnishing,
tanning,
lacquering, and which supply the shop of the druggist with
medicines and
with poisons.
There is another analogy, which would seem to associate plants with
animals, and which perhaps belongs to this Note on Glandulation, I
mean
the similarity of their digestive powers. In the roots of growing
vegetables, as in the process of making malt, the farinaceous part
of
the seed is converted into sugar by the vegetable power of
digestion in
the same manner as the farinaceous matter of seeds are converted
into
sweet chyle by the animal digestion. The sap-juice which rises in
the
vernal months from the roots of trees through the alburnum or
sap-wood,
owes its sweetness I suppose to a similar digestive power of the
absorbent system of the young buds. This exists in many vegetables
in
great abundance as in vines, sycamore, birch, and most abundantly
in the
palm-tree, (Isert's Voyage to Guinea,) and seems to be a similar
fluid
in all plants, as chyle is similar in all animals.
Hence as the digested food of vegetables consists principally of
sugar,
and from that is produced again their mucilage, starch, and oil,
and
since animals are sustained by these vegetable productions, it
would
seem that the sugar-making process carried on in vegetable vessels
was
the great source of life to all organized beings. And that if our
improved chemistry should ever discover the art of making sugar
from
fossile or aerial matter without the assistance of vegetation, food
for
animals would then become as plentiful as water, and mankind might
live
upon the earth as thick as blades of grass, with no restraint to
their
numbers but the want of local room.
It would seem that roots fixed in the earth, and leaves innumerable
waving in the air were necessary for the decomposition of water,
and the
conversion of it into saccharine matter, which would have been not
only
cumberous but totally incompatible with the locomotion of animal
bodies.
For how could a man or quadruped have carried on his head or back a
forest of leaves, or have had long branching lacteal or absorbent
vessels terminating in the earth? Animals therefore subsist on
vegetables; that is, they take the matter so far prepared, and have
organs to prepare it further for the purposes of higher animation,
and
greater sensibility. In the same manner the apparatus of green
leaves
and long roots were found inconvenient for the more animated and
sensitive parts of vegetable-flowers, I mean the anthers and
stigmas,
which are therefore separate beings, endued with the passion and
power
of reproduction, with lungs of their own, and fed with honey, a
food
ready prepared by the long roots and green leaves of the plant, and
presented to their absorbent mouths.
From this outline a philosopher may catch a glimpse of the general
economy of nature; and like the mariner cast upon an unknown shore,
who
rejoiced when he saw the print of a human foot upon the sand, he
may cry
out with rapture, “A GOD DWELLS HERE.”
CONTENTS
OF THE
ADDITIONAL
There are four strata of the atmosphere, and four kinds of meteors.
1.
Lightning is electric, exists in visible clouds, its short course,
and
red light. 2. Shooting stars exist in invisible vapour, without
sound,
white light, have no luminous trains. 3. Twilight; fire-balls move
thirty miles in a second, and are about sixty miles high, have
luminous
trains, occasioned by an electric spark passing between the aerial
and
inflammable strata of the atmosphere, and mixing them and setting
them
on fire in its passage; attracted by volcanic eruptions; one
thousand
miles through such a medium resists less than the tenth of an inch
of
glass. 4. Northern lights not attracted to a point but diffused;
their
colours; passage of electric fire in vacuo dubious; Dr. Franklin's
theory of northern lights countenanced in part by the supposition
of
a superior atmosphere of inflammable air; antiquity of their
appearance;
described in Maccabees.
The rainbow was in part understood before Sir Isaac Newton; the
seven
colours were discovered by him; Mr. Gallon's experiments on
colours;
manganese and lead produce colourless glass.
The rays refracted by the convexity of the atmosphere; the
particles of
air and of water are blue; shadow by means of a candle in the day;
halo
round the moon in a fog; bright spot in the cornea of the eye;
light
from cat's eyes in the dark, from a horse's eyes in a cavern,
coloured
by the choroid coat within the eye.
Tails of comets from rarified vapour, like northern lights, from
electricity; twenty millions of miles long; expected comet.
Dispute about phlogiston; the sun the fountain from whence all
phlogiston is derived; its rays not luminous till they arrive at
our
atmosphere; light owing to their combustion with air, whence an
unknown
acid; the sun is on fire only on its surface; the dark spots on it
are
excavations through its luminous crust.
Sun's heat much less than that from the fire at the earth's centre;
sun's heat penetrates but a few feet in summer; some mines are
warm;
warm springs owing to subterraneous fire; situations of volcanos on
high
mountains; original nucleus of the earth; deep vallies of the
ocean;
distant perception of earthquakes; great attraction of mountains;
variation of the compass; countenance the existence of a cavity or
fluid
lava within the earth.
Combined and sensible heat; chemical combinations attract heat,
solutions reject heat; ice cools boiling water six times as much as
cold
water cools it; cold produced by evaporation; heat by devaporation;
capacities of bodies in respect to heat, 1. Existence of the matter
of
heat shewn from the mechanical condensation and rarefaction of air,
from
the steam produced in exhausting a receiver, snow from rarefied
air,
cold from discharging an air-gun, heat from vibration or friction;
2.
Matter of heat analogous to the electric fluid in many
circumstances,
explains many chemical phenomena.
Mechanical impulse of light dubious; a glass tube laid horizontally
before a fire revolves; pulse-glass suspended on a centre; black
leather
contracts in the sunshine; Memnon's statue broken by Cambyses.
Eighteen species of glow-worm, their light owing to their
respiration in
transparent lungs; Acudia of Surinam gives light enough to read and
draw
by, use of its light to the insect; luminous sea-insects adhere to
the
skin of those who bathe in the ports of Languedoc, the light may
arise
from putrescent slime.
Discovered by Kunkel, Brandt, and Boyle; produced in respiration,
and by
luminous insects, decayed wood, and calcined shells; bleaching a
slow
combustion in which the water is decomposed; rancidity of animal
fat
owing to the decomposition of water on its surface; aerated marine
acid
does not whiten or bleach the hand.
Hero of Alexandria first applied steam to machinery, next a French
writer in 1630, the Marquis of Worcester in 1655, Capt. Savery in
1689,
Newcomen and Cawley added the piston; the improvements of Watt and
Boulton; power of one of their large engines equal to two hundred
horses.
Expansion of water in freezing; injury done by vernal frosts; fish,
eggs, seeds, resist congelation; animals do not resist the increase
of
heat; frosts do not meliorate the ground, nor are in general
salubrious;
damp air produces cold on the skin by evaporation; snow less
pernicious
to agriculture than heavy rains for two reasons.
1. Points preferable to knobs for defence of buildings; why
points
emit the electric fluid; diffusion of oil on water; mountains are
points
on the earth's globe; do they produce ascending currents of air? 2.
Fairy-rings explained; advantage of paring and burning
ground.
A tree is a swarm of individual plants; vegetables are either
oviparous
or viviparous; are all annual productions like many kinds of
insects?
Hybernacula, a new bark annually produced over the old one in trees
and
in some herbaceous plants, whence their roots seem end-bitten; all
bulbous roots perish annually; experiment on a tulip-root; both the
leaf-bulbs and the flower-bulbs are annually renewed.
The spots in the sun are cavities, some of them four thousand miles
deep
and many times as broad; internal parts of the sun are not in a
state of
combustion; volcanos visible in the sun; all the planets together
are
less than one six hundred and fiftieth part of the sun; planets
were
ejected from the sun by volcanos; many reasons shewing the
probability
of this hypothesis; Mr. Buffon's hypothesis that planets were
struck off
from the sun by comets; why no new planets are ejected from the
sun;
some comets and the georgium sidus may be of later date; Sun's
matter
decreased; Mr. Ludlam's opinion, that it is possible the moon might
be
projected from the earth.
High mountains and deep mines replete with shells; the earth's
nucleus
covered with limestone; animals convert water into limestone; all
the
calcareous earth in the world formed in animal and vegetable
bodies;
solid parts of the earth increase; the water decreases; tops of
calcareous mountains dissolved; whence spar, marbles, chalk,
stalactites; whence alabaster, fluor, flint, granulated limestone,
from
solution of their angles, and by attrition; tupha deposited on
moss;
limestones from shells with animals in them; liver-stone from
fresh-
water muscles; calcareous earth from land-animals and vegetables,
as
marl; beds of marble softened by fire; whence Bath-stone contains
lime
as well as limestone.
The production of morasses from fallen woods; account by the Earl
Cromartie of a new morass; morasses lose their salts by solution in
water; then their iron; their vegetable acid is converted into
marine,
nitrous, and vitriolic acids; whence gypsum, alum, sulphur; into
fluor-
acid, whence fluor; into siliceous acid, whence flint, the sand of
the
sea, and other strata of siliceous sand and marl; some morasses
ferment
like new hay, and, subliming their phlogistic part, form coal-beds
above
and clay below, which are also produced by elutriation; shell-fish
in
some morasses, hence shells sometimes found on coals and over iron-
stone.
Calciform ores; combustion of iron in vital air; steel from
deprivation
of vital air; welding; hardness; brittleness like Rupert's drops;
specific levity; hardness and brittleness compared; steel tempered
by
its colours; modern production of iron, manganese, calamy; septaria
of
iron-stone ejected from volcanos; red-hot cannon balls.
1. Siliceous rocks from morasses; their cements. 2.
Siliceous trees;
coloured by iron or manganese; Peak-diamonds; Bristol-stones; flint
in
form of calcareous spar; has been fluid without much heat; obtained
from
powdered quartz and fluor-acid by Bergman and by Achard. 3.
Agates and
onyxes found in sand-rocks; of vegetable origin; have been in
complete
fusion; their concentric coloured circles not from superinduction
but
from congelation; experiment of freezing a solution of blue
vitriol;
iron and manganese repelled in spheres as the nodule of flint
cooled;
circular stains of marl in salt-mines; some flint nodules resemble
knots
of wood or roots. 4. Sand of the sea; its acid from
morasses; its base
from shells. 5. Chert or petrosilex stratified in cooling;
their
colour and their acid from sea-animals; labradore-stone from
mother-
pearl. 6. Flints in chalk-beds; their form, colour, and
acid, from the
flesh of sea-animals; some are hollow and lined with crystals;
contain
iron; not produced by injection from without; coralloids converted
to
flint; French-millstones; flints sometimes found in solid strata.
7.
Angles of sand destroyed by attrition and solution in steam;
siliceous
breccia cemented by solution in red-hot water. 8. Basaltes and
granites are antient lavas; basaltes raised by its congelation
not by
subterraneous fire.
Fire and water two great agents; stratification from precipitation;
many
stratified materials not soluble in water. 1. Stratification of
lava
from successive accumulation. 2. Stratifications of limestone from
the
different periods of time in which the shells were deposited. 3.
Stratifications of coal, and clay, and sandstone, and iron-ores,
not
from currents of water, but from the production of morass-beds at
different periods of time; morass-beds become ignited; their
bitumen and
sulphur is sublimed; the clay, lime, and iron remain; whence sand,
marle, coal, white clay in valleys, and gravel-beds, and some
ochres,
and some calcareous depositions owing to alluviation; clay from
decomposed granite; from the lava of Vesuvius; from vitreous lavas.
Rose-colour and purple from gold; precipitates of gold by alcaline
salt
preferable to those by tin; aurum fulminans long ground; tender
colours
from gold or iron not dissolved but suspended in the glass;
cobalts;
calces of cobalt and copper require a strong fire; Ka-o-lin and
Pe-tun-tse the same as our own materials.
Its figures do not allude to private history; they represent a part
of
the Elusinian mysteries; marriage of Cupid and Psyche; procession
of
torches; the figures in one compartment represent MORTAL LIFE in
the act
of expiring, and HUMANKIND attending to her with concern; Adam and
Eve
hyeroglyphic figures; Abel and Cain other hyeroglyphic figures; on
the
other compartment is represented IMMORTAL LIFE, the Manes or Ghost
descending into Elisium is led on by DIVINE LOVE, and received by
IMMORTAL LIFE, and conducted to Pluto; Tree of Life and Knowledge
are
emblematical; the figure at the bottom is of Atis, the first great
Hierophant, or teacher of mysteries.
1. A fountain of fossile tar in Shropshire; has been distilled from
the
coal-beds beneath, and condensed in the cavities of a sand-rock;
the
coal beneath is deprived of its bitumen in part; bitumen sublimed
at
Matlock into cavities lined with spar. 2. Coal has been exposed to
heat;
woody fibres and vegetable seeds in coal at Bovey and Polesworth;
upper
part of coal-beds more bituminous at Beaudesert; thin stratum of
asphaltum near Caulk; upper part of coal-bed worse at Alfreton;
upper
stratum of no value at Widdrington; alum at West-Hallum; at
Bilston. 3.
Coal at Coalbrooke-Dale has been immersed in the sea, shewn by sea-
shells; marks of violence in the colliery at Mendip and at Ticknal;
Lead-ore and spar in coal-beds; gravel over coal near Lichfield;
Coal
produced from morasses shewn by fern-leaves, and bog-shells, and
muscle-
shells; by some parts of coal being still woody; from Lock Neagh
and
Bovey, and the Temple of the devil; fixed alcali; oil.
Granite the lowest stratum of the earth yet known; porphory, trap,
Moor-
stone, Whin-stone, slate, basaltes, all volcanic productions
dissolved
in red-hot water; volcanos in granite strata; differ from the heat
of
morasses from fermentation; the nucleus of the earth ejected from
the
sun? was the sun originally a planet? supposed section of the
globe.
I. Solution of water in air; in the matter of heat; pulse-glass. 2.
Heat
is the principal cause of evaporation; thermometer cooled by
evaporation
of ether; heat given from steam to the worm-tub; warmth
accompanying
rain. 3. Steam condensed on the eduction of heat; moisture on cold
walls; south-west and north-east winds. 4. Solution of salt and of
blue
vitriol in the matter of heat. II. Other vapours may precipitate
steam
and form rain. 1. Cold the principal cause of devaporation; hence
the
steam dissolved in heat is precipitated, but that dissolved in air
remains even in frosts; south-west wind. 2. North-east winds mixing
with
south-west winds produce rain; because the cold particles of air of
the
north-east acquire some of the matter of heat from the south-west
winds.
3. Devaporation from mechanical expansion of air, as in the
receiver of
an air-pump; summer-clouds appear and vanish; when the barometers
sink
without change of wind the weather becomes colder. 4. Solution of
water
in electric fluid dubious. 5. Barometer sinks from the lessened
gravity
of the air, and from the rain having less pressure as it falls; a
mixture of a solution of water in calorique with an aerial solution
of
water is lighter than dry air; breath of animals in cold weather
why
condensed into visible vapour and dissolved again.
Lowest strata of the earth appear on the highest hills; springs
from
dews sliding between them; mountains are colder than plains; 1.
from
their being insulated in the air; 2. from their enlarged surface;
3.
from the rarety of the air it becomes a better conductor of heat;
4. by
the air on mountains being mechanically rarefied as it ascends; 5.
gravitation of the matter of heat; 6. the dashing of clouds against
hills; of fogs against trees; springs stronger in hot days with
cold
nights; streams from subterranean caverns; from beneath the snow on
the
Alps.
The armour of the Echinus moveable; holds itself in storms to
stones by
1200 or 2000 strings: Nautilus rows and sails; renders its shell
buoyant: Pinna and Cancer; Byssus of the antients was the beard of
the
Pinna; as fine as the silk is spun by the silk-worm; gloves made of
it;
the beard of muscles produces sickness; Indian weed; tendons of
rats
tails.
Sturgeon's mouth like a purse; without teeth; tendrils like worms
hang
before his lips, which entice small fish and sea-insects mistaking
them
for worms; his skin used for covering carriages; isinglass made
from it;
cavear from the spawn.
Oil and water do not touch; a second drop of oil will not diffuse
itself
on the preceeding one; hence it stills the waves; divers for pearl
carry
oil in their mouths; oil on water produces prismatic colours; oiled
cork
circulates on water; a phial of oil and water made to oscillate.
The Teredo has calcareous jaws; a new enemy; they perish when they
meet
together in their ligneous canals; United Provinces alarmed for the
piles of the banks of Zeland; were destroyed by a severe winter.
A whirlpool on the coast of Norway; passes through a subterraneous
cavity; less violent when the tide is up; eddies become hollow in
the
middle; heavy bodies are thrown out by eddies; light ones retained;
oil
and water whirled in a phial; hurricanes explained.
Snow in contact with the earth is in a state of thaw; ice-houses;
rivers
from beneath the snow; rime in spring vanishes by its contact with
the
earth; and snow by its evaporation and contact with the earth; moss
vegetates beneath the snow; and Alpine plants perish at Upsal for
want
of show.
Air is perpetually subject to increase and to diminution; Oxygene
is
perpetually produced from vegetables in the sunshine, and from
clouds in
the light, and from water; Azote is perpetually produced from
animal and
vegetable putrefaction, or combustion; from springs of water;
volatile
alcali; fixed alcali; sea-water; they are both perpetually
diminished by
their contact with the soil, producing nitre; Oxygene is diminished
in
the production of all acids; Azote by the growth of animal bodies;
charcoal in burning consumes double its weight of pure air; every
barrel
of red-lead absorbes 2000 cubic feet of vital air; air obtained
from
variety of substances by Dr. Priestley; Officina aeris in the polar
circle, and at the Line. South-west winds; their westerly
direction
from the less velocity of the earth's surface; the contrary in
respect
to north-east winds; South-west winds consist of regions of air
from the
south; and north-east winds of regions of air from the north; when
the
south-west prevails for weeks and the barometer sinks to 28, what
becomes of above one fifteenth part of the atmosphere; 1. It is not
carried back by superior currents; 2. Not from its loss of
moisture; 3.
Not carried over the pole; 4. Not owing to atmospheric tides or
mountains; 5. It is absorbed at the polar circle; hence south-west
winds
and rain; south-west sometimes cold. North-east winds
consist of air
from the north; cold by the evaporation of ice; are dry winds; 1.
Not
supplied by superior current; 2. The whole atmosphere increased in
quantity by air set at liberty from its combinations in the polar
circles. South-east winds consist of north winds driven
back. North-
west winds consist of south-west winds driven back; north-west
winds of
America bring frost; owing to a vertical spiral eddy of air between
the
eastern coast and the Apalachian mountains; hence the greater cold
of
North America. Trade-winds; air over the Line always hotter
than at
the tropics; trade-winds gain their easterly direction from the
greater
velocity of the earth's surface at the line; not supplied by
superior
currents; supplied by decomposed water in the sun's great light; 1.
Because there are no constant rains in the tract of the
trade-winds; 2.
Because there is no condensible vapour above three or four miles
high at
the line. Monsoons and tornadoes; some places at the tropic
become
warmer when the sun is vertical than at the line; hence the air
ascends,
supplied on one side by the north-east winds, and on the other by
the
south-west; whence an ascending eddy or tornado, raising water from
the
sea, or sand from the desert, and incessant rains; air diminished
to the
northward produces south-west winds; tornadoes from heavier air
above
sinking through lighter air below, which rises through a
perforation;
hence trees are thrown down in a narrow line of twenty or forty
yards
broad, the sea rises like a cone, with great rain and lightning.
Land
and sea breezes; sea less heated than land; tropical islands
more
heated in the day than the sea, and are cooled more in the night.
Conclusion; irregular winds from other causes; only two
original winds
north and south; different sounds of north-east and south-west
winds; a
Bear or Dragon in the arctic circle that swallows at times and
disembogues again above one fifteenth part of the atmosphere; wind-
instruments; recapitulation.
Pure air from Dr. Priestley's vegetable matter, and from vegetable
leaves, owing to decomposition of water; the hydrogene retained by
the
vegetables; plants in the shade are tanned green by the
sun's light;
animal skins are tanned yellow by the retention of
hydrogene; much
pure air from dew on a sunny morning; bleaching why sooner
performed on
cotton than linen; bees wax bleached; metals calcined by
decomposition
of water; oil bleached in the light becomes yellow again in the
dark;
nitrous acid coloured by being exposed to the sun; vegetables
perspire
more than animals, hence in the sun-shine they purify air more by
their
perspiration than they injure it by their respiration; they grow
fastest
in their sleep.
Buds the viviparous offspring of vegetables; placentation in bulbs
and
seeds; placentation of buds in the roots, hence the rising of sap
in the
spring, as in vines, birch, which ceases as soon as the leaves
expand;
production of the leaf of Horse-chesnut, and of its new bud; oil of
vitriol on the bud of Mimosa killed the leaf also; placentation
shewn
from the sweetness of the sap; no umbilical artery in vegetables.
Buds set in the ground will grow if prevented from bleeding to
death by
a cement; vegetables require no muscles of locomotion, no stomach
or
bowels, no general system of veins; they have, 1. Three systems of
absorbent vessels; 2. Two pulmonary systems; 3. Arterial systems;
4.
Glands; 5. Organs of reproduction; 6. muscles. I. Absorbent system
evinced by experiments by coloured absorptions in fig-tree and
picris;
called air-vessels erroneously; spiral structure of absorbent
vessels;
retrograde motion of them like the throats of cows. II. Pulmonary
arteries in the leaves, and pulmonary veins; no general system of
veins
shewn by experiment; no heart; the arteries act like the vena
portarum
of the liver; pulmonary system in the petals of flowers;
circulation
owing to living irritability; vegetable absorption more powerful
than
animal, as in vines; not by capillary attraction.
I. Leaves not perspiratory organs, nor excretory ones; lungs of
animals.
1. Great surfaces of leaves. 2. Vegetable blood changes colour in
the
leaves; experiment with spurge; with picris. 3. Upper surface of
the
leaf only acts as a respiratory organ. 4. Upper surface repels
moisture;
leaves laid on water. 5. Leaves killed by oil like insects; muscles
at
the foot-stalks of leaves. 6. Use of light to vegetable leaves;
experiments of Priestley, Ingenhouze, and Scheel. 7. Vegetable
circulation similar to that of fish. II. Another pulmonary system
belongs to flowers; colours of flowers. 1. Vascular structure of
the
corol. 2. Glands producing honey, wax, &c. perish with the corol.
3.
Many flowers have no green leaves attending them, as Colchicum. 4.
Corols not for the defence of the stamens. 5. Corol of Helleborus
Niger
changes to a calyx. 6. Green leaves not necessary to the fruit-bud;
green leaves of Colchicum belong to the new bulb not to the flower.
7.
Flower-bud after the corol falls is simply an uterus; mature
flowers not
injured by taking of the green leaves. 8. Inosculation of vegetable
vessels.
Seeds in broom discovered twenty days before the flower opens;
progress
of the seed after impregnation; seeds exist before fecundation;
analogy
between seeds and eggs; progress of the egg within the hen; spawn
of
frogs and of fish; male Salamander; marine plants project a liquor
not a
powder; seminal fluid diluted with water, if a stimulus only? Male
and
female influence necessary in animals, insects, and vegetables,
both in
production of seeds and buds; does the embryon seed produce the
surrounding fruit, like insects in gall-nuts?
Vegetable glands cannot be injected with coloured fluids; essential
oil;
wax; honey; nectary, its complicate apparatus; exposes the honey to
the
air like the lacrymal gland; honey is nutritious; the male and
female
parts of flowers copulate and die like moths and butterflies, and
are
fed like them with honey; anthers supposed to become insects;
depredation of the honey and wax injurious to plants; honey-dew;
honey
oxygenated by exposure to air; necessary for the production of
sensibility; the provision for the embryon plant of honey, sugar,
starch, &c. supplies food to numerous classes of animals; various
vegetable secretions as gum tragacanth, camphor, elemi, anime,
turpentine, balsam of Mecca, aloe, myrrh, elastic resin, manna,
sugar,
wax, tallow, and many other concrete juices; vegetable digestion;
chemical production of sugar would multiply mankind; economy of
nature.
THE END